Best Mcdonnell & Miller in 2026

Last Updated: Sep 27, 2023

At a Glance: Our Top Picks

McDonnell & Miller FS4-3 General Purpose Liquid Flow Switch
#TOP1
Mcdonnell & Miller Fs4-3 General Purpose Liquid Flow
5.8
PM SCORE
Mcdonnell & Miller Switch, Liquid Flow
#TOP2
Mcdonnell & Miller Switch, Liquid Flow
5.1
PM SCORE
Mcdonnell & Miller, FS8-W, Flow Switch, 1 in Nema
#TOP3
Mcdonnell & Miller, Fs8-W, Flow Switch, 1 In
4.6
PM SCORE

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Summary of the best Mcdonnell & Miller of 2026

Mcdonnell & Miller Fs4-3 General Purpose Liquid Flow Switch

MCDONNELL & MILLER
114400
1.00 X 1.00 X 1.00 Inches
2.00 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Maintak 9.77

Features

For starting or stopping electrically operated equipment such as signal lights, alarms, motors, automatic burners, metering devices and others

1" NPT

Minimum/maximum temperature: 32 degrees F/300 degrees F

Sensitivity adjusting screw makes flow adjustment easy

Four stainless steel paddles included: 1", 2", 3" & 6" (25, 50, 80, & 150mm)

#TOP2

Mcdonnell & Miller Switch, Liquid Flow

MCDONNELL & MILLER
FS5-3/4
7.38 X 5.63 X 5.38 Inches
5.05 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Neobits_ 8.88

Features

Pumps

Manufacturer: Mcdonnell & Miller

Made in: United States

Mcdonnell & Miller, Fs8-W, Flow Switch, 1 In Nema

MCDONNELL & MILLER
FS8-W
3.25 X 3.25 X 8.38 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
The Portland Group 9.89

Features

package height :26.67 cm

package length :10.795 cm

package width :10.795 cm

country of origin :United States

Mcdonnell & Miller Fs251 General Purpose Flow Switch, 1" Replaces Fs4-3

MCDONNELL & MILLER
FS251
8.40 X 4.10 X 3.60 Inches
2.00 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Voomi Supply 9.07

Features

Product Type :Electronic Component

Package Dimensions :9.1 Cm L X10.4 Cm W X21.3 Cm H

Country Of Origin :United States

Package Weight :1.0Lbs

Flow Switch Assembly Glx-Flo-Rp For Hayward Goldline Aquarite Salt System, Pool Flow Sensor Suitable For Hayward Salt Cell And Chlorine Generator, With 15-Foot Cable Flow Switch

COOOUDS
GLX-FLO-RP
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
beezoom 9.92

Features

【Compatible】 This GLX-FLO-RP flow switch can compatible with all the salt chlorine generator systems of Hayward and Goldline. GLX-FLO-RP flow switch replacement can be used with Hayward Goldline Salt Chlorination Turbo Cell.

【Suitable Models】The swimming pool flow switch suitable for almost all Hayward Goldline salty system,Hayward part GLX-FLO-RP can replace GLXFLORP, GLX-FLO-HP, Q-12DS-C2, OPT-F/S. Suitable for : Pro Logic, Mineral Springs, Mineral Springs MS10/MS11, Aqua Plus, Aqua Rite XL, Aqua Logic, Aqua Rite Pro, Aqua Rite compatible, Aqua Plus, H40, SwimPurePlus, SplashCLEAR, SmartPure, Splash SP-40...

【Accessories】 The water flow sensor hayward GLX-FLO-RP has a 15-Foot Cable. One end is a standard Phone Jack connection and it has a circle gasket and a round of tape.

【Easy to install】 Hayward flow switch assembly has fewer integral parts and is easy to install. Just insert the two ends of the flow switch with cable into the correspondingly correct positions. Unplug existing (old) flow sensor, wrap enough tape and screw the switch into Run pump, do not overtighten it. It may only take 2 minutes to install.

【Services】 We provide 1 year of quality service and consultation services, if you have any questions, please E-mail us, we will reply within 12 hours.

#TOP6

Elecall Stainless Steel Tank Water Level Sensor Float Switch 110V Es7510

ELECALL
6930246703684
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
ELECALL TOOLS 8.50

Features

Product Name : Water Level Sensor;Stainless steel Material;Contacts : NO+NC;Max Contact Rating : 10W Wire length:12inch, Max Breakdown Voltage: 110V AC/DC;

It does not have a complex circuit,will not be disturbed,as long as the material selection,liquid,pressure or temperture can be used in any environment.

This float switch is a device used to sense the level of liquid within a tank,the switch may activate a pump,an indicator,an alarm,or other device,but need to be used with relay

The float level switch is widely used in electronic,electrical,chemical,water treatment,drainage and other walks of life level control and alarm. Material:Stainless Steel.

The versatility of this vertically monted sensor means that it can be installed either at the top or base of your tank,depending on whether you wish to detect the water's rise or fall.

#TOP7

Elecall 4" Stainless Steel Tank Water Level Sensor Float Switch Es10010-2-50 110V The Water Level Distance Between The Two Floats Is 2"

ELECALL
6930246703585
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
ELECALL TOOLS 8.66

Features

Product Name : Water Level Sensor;Stainless steel Material;Contacts : NO+NC;Max Contact Rating : 10W,The float has two floating ball devices, which can be used to control the water level within a certain range

It does not have a complex circuit,will not be disturbed,as long as the material selection,liquid,pressure or temperture can be used in any environment.

This float switch is a device used to sense the level of liquid within a tank,the switch may activate a pump,an indicator,an alarm,or other device,but need to be used with relay

The float level switch is widely used in electronic,electrical,chemical,water treatment,drainage and other walks of life level control and alarm. Material:Stainless Steel. Alternating current: 223v.

The versatility of this vertically monted sensor means that it can be installed either at the top or base of your tank,depending on whether you wish to detect the water's rise or fall.

Elecall 4"Float Switch Stainless Steel Tank Water Level Sensor 110V Es10010 Wire Length 12Inch

ELECALL
6930246703608
0.11 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
ELECALL TOOLS 8.41

Features

Product Name : Water Level Sensor;Stainless steel Material;Contacts : NO+NC;Max Contact Rating : 10W

It does not have a complex circuit,will not be disturbed,as long as the material selection,liquid,pressure or temperture can be used in any environment.

This float switch is a device used to sense the level of liquid within a tank,the switch may activate a pump,an indicator,an alarm,or other device,but need to be used with relay

The float level switch is widely used in electronic,electrical,chemical,water treatment,drainage and other walks of life level control and alarm. Material:Stainless Steel. Alternating current: 223v.

The versatility of this vertically monted sensor means that it can be installed either at the top or base of your tank,depending on whether you wish to detect the water's rise or fall.

Digiten Fs-C02 G3/4" Bsp Male Thread Brass Water Flow Switch 1-30L/Min, 0-2A/ 0-220V(Ac Or Dc)

DIGITEN
FS-C02ZJ
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
SENSTREE 9.54

Features

🌟🌊【Safe and Reliable】This flow sensor switch is made of brass, all materials are in line with ROHS testing standards. It's a safety device that shuts off the current to the device (heaters, pumps, etc.) when it senses no water flow.When connecting the load, please add a relay.

🌟💧【Thread type: 3/4" BSP Male Thread】 The flow sensor `s male thread external diameter: 25.85mm.It is fit in NPT Thread if you connect them with teflon

🌟🌊 【Easy to install 】Our flow sensor is waterproof, heat resistance, pressurresistance, cold resistance, small size, stable and reliable.

🌟💧 【Specification】Operation voltage of this flow sensor is : 0-220V(AC or DC), Working current: 0-2A, max working pressure: 1.75 MPa. Flow range: 1-30L/min.

🌟🌊 【Widely Applications 】This water flow sensor switch can be use for Water heaters, pumps, hot tub, boiler, water dispensers, coffee machines, hot card machines, steam equipment, water system, the campus card sales, selling self-help water systems, water treatment equipment, cooling systems, mechanical equipment, instrumentation, pharmaceutical equipment.

General Pump 100975 Flow Switch, 12.0 Gpm, 5000 Psi

GENERAL PUMP
100975
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Disilia 5.20

Features

Max Switch Voltage: 250 VAC

Max Switching Current: 5 AMPS

Resistance with Leads: 30 OHM

Electrical Service Life: 200,000 Cycles

Mechanical Service Life: 10,000,000 Cycles

Mcdonnell & Miller Fs4-3 General Purpose Liquid Flow Switch

MCDONNELL & MILLER
114400
1.00 X 1.00 X 1.00 Inches
2.00 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Maintak 9.77

Features

For starting or stopping electrically operated equipment such as signal lights, alarms, motors, automatic burners, metering devices and others

1" NPT

Minimum/maximum temperature: 32 degrees F/300 degrees F

Sensitivity adjusting screw makes flow adjustment easy

Four stainless steel paddles included: 1", 2", 3" & 6" (25, 50, 80, & 150mm)

Johnson Controls F261Mah-V01C Flow Switch

JOHNSON CONTROLS
F261MAH-V01C
12.25 X 4.50 X 4.50 inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
SUPPLIESPLUSTORE 6.36

Features

Type 3R (NEMA) or Type 4 (NEMA) enclosure allows use in indoor or outdoor applications

Viton diaphragms allow use in fluid lines carrying chlorinated water, treated water, or other nonhazardous fluids

low-flow operation on low-flow models actuates switch with less than 1.0 GPM (3.8 L/min) flow for water applications or 9.0 GPM (34.1 L/min) flow for steam applications

Maximum fluid pressure of 290 psig (20 bar) permits use in a wide range of pressure flow conditions

Uxcell G1/4" Hall Effect Water Flow Sensor Switch Flowmeter Counter Fluid Meter Dc5V 0.2-2.5L/Min Sen-Hz41W

UXCELL
A18041200UX0138
5.51 X 3.94 X 0.79 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
uxcell 9.95

Features

Light weight, small size, easy to install.Hall element is imported, water-proof design to prevent water ingress,The inside of the impeller is inlaid with a stainless steel shaft and is always wear-resistant.

All materials are in line with SGS testing standards.

Three wire connection: Red for positive, black for negative, yellow for pulse signal.

The water flow sensor is applied for water heater, and can be used as flow switch.

Maximum water pressure: 1.2MPa, flow range: 0.2-2.5L/min

#TOP14

Mcdonnell & Miller Switch, Liquid Flow

MCDONNELL & MILLER
FS5-3/4
7.38 X 5.63 X 5.38 Inches
5.05 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Neobits_ 8.88

Features

Pumps

Manufacturer: Mcdonnell & Miller

Made in: United States

Trane Switch, Flow Sensor Thermal Disp. 24 Va

TRANE
SWT03335
3.45 X 2.55 X 2.50 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Amazon.com 9.68

Features

This is a genuine OEM (Original Equipment Manufacturer) part.

Use genuine OEM parts for safety reliability and performance

Ywbl-Wh Hfs-25 1Inch Thread Paddle Type Liquid Water Flow Paddle Control Switch Spt Ac220V 15A With Paddles, Flow Switch

YWBL-WH
YWBL-WH5BT8C4IF2K1271
0.39 X 0.39 X 0.39 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Partgry-T 9.71

Features

Used in water treatment systems, central air conditioning, water‑cooled units and other fields.

Suitable for water, ethylene glycol and any other liquid that has no corrosive effect on brass and phosphor bronze and has no effect on sealing performance.

The flow switch has the characteristics of high sensitivity and strong durability, practical for use.

Medium temperature is 0‑60 ℃, contact life is about 100,000 times, rated pressure is 10bar.

Made of high quality brass material, high hardness and strength, wear‑resistant and durable.

Uxcell 1/4" Hall Effect Water Flow Sensor Switch Flowmeter Counter Fluid Meter Dc5V 0.15-1.5L/Min Sen-Hz06K

UXCELL
A18041200UX0134
5.51 X 3.94 X 1.18 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
uxcell 9.95

Features

Light weight, small size, easy to install.Hall element is imported, water-proof design to prevent water ingress,The inside of the impeller is inlaid with a stainless steel shaft and is always wear-resistant.

All materials are in line with SGS testing standards.

Three wire connection: Red for positive, black for negative, yellow for pulse signal.

The water flow sensor is applied for water heater, and can be used as flow switch.

Maximum water pressure: 1.2MPa, flow range: 0.15-1.5L/min.

W.e. Anderson® Vane Flow Switch, Fs-2, 1" Mnpt, Low Cost, Field Adjustable Set Point & Paddle

DWYER
FS-2
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Blackhawk Supply 5.30

Features

Wetted Materials: Bellow: Tin-bronze; Vane: Stainless steel; Body: Forged brass

Temperature Limits: 230°F (110°C)

Pressure Limits: 145 psig (10 bar)

Switch Type: SPDT snap switch

Enclosure Rating: NEMA 4 (IP64)

Hfs-25 1"/Dn25 Flow Switch,Liquid Water Flow Paddle Control Switch Spdt Contacts 6-380V

YWBL-WH
YWBL-WHY7WXQC2410
3.35 X 2.56 X 4.92 Inches
1.15 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Partgry-T 9.71

Features

This flow switch is made of high quality stainless steel, corrosion resistant and long service life.

This product is used to measure the fluid dynamics of fluids passing through pipes, such as water, ethylene diluents, glycols and other liquids that do not corrode copper.

This water flow switch is suitable for water treatment systems, central air conditioning, water cooling units, fire protection systems and other fields.

Flow switches are typically used in locations that require interlocking or "cut" protection.

When the flow exceeds the set value, the fluid drives the blade and the microswitch, and the SPDT contact can connect the circuit and disconnect other circuits.

Hilitand 1/2" Water Flow Switch, Hfs-15 Adjustable Thread Double Throw Spdt 220Vac 15A Water Flow Control 1.0Mpa

HILITAND
HILITANDP7TUY5R328
3.35 X 2.56 X 4.92 Inches
0.90 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
tanus 9.70

Features

HIGH QUALITY: It adopts premium material, with strong temperature adaptability of 0~ 120, and can withstand high pressure of 1.0Mpa.

ADJUSTABLE: The flow control value is adjustable and the action repetition point is stable.

MEASURE LIQUID: The product is used to measure the dynamic state of the liquid flowing through the pipeline, such as: water, ethylene, ethylene glycol and other liquids that have no corrosive effect on copper

APPLICATION: It is application for water treatment system, central air conditioning, water cooling unit, fire protection system and other fields.

Mcdonnell & Miller, Fs8-W, Flow Switch, 1 In Nema

MCDONNELL & MILLER
FS8-W
3.25 X 3.25 X 8.38 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
The Portland Group 9.89

Features

package height :26.67 cm

package length :10.795 cm

package width :10.795 cm

country of origin :United States

#TOP22

Yxq 300Mm Stainless Steel Float Switch 2 Channel Liquid Water Level Sensor Monitor Vertical Fish Tank Mini M10

YXQ
LMT12021019
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
WLG Electrical 9.83

Features

ES30010-2 Stainless Steel Water Level Sensor;Max Contact Rating :10W

Max Switching Voltage : 100 DC;Max Switching Current : 0.5A;Max Breakdown Voltage : 220VDC;Max Carry Current : 1A

Design: Double Ball; Put In Water Length: 300mm/12";Total Length: 315mm/12.5"

Thread Dia(Approx) : M10;Float Ball Size: 26 x 26mm/1" x 1"(L*D);Cable Length : 35cm / 14"

Max Contact Resistance : 100mΩ;Temperature Rating : -30℃ +125℃

Mcdonnell & Miller Fs251 General Purpose Flow Switch, 1" Replaces Fs4-3

MCDONNELL & MILLER
FS251
8.40 X 4.10 X 3.60 Inches
2.00 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Voomi Supply 9.07

Features

Product Type :Electronic Component

Package Dimensions :9.1 Cm L X10.4 Cm W X21.3 Cm H

Country Of Origin :United States

Package Weight :1.0Lbs

Raypak Flow Switch, 1 In, 24V

CAI - RAYPAK
007142F
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
MyPoolYard 9.73

Water Flow Switch, Lkb-01D Water Flow Switch 250V 15A Rc1 "Two Way Water Flow Switch Ip54 Flow Switch Flow Valve 1.0Mpa Spdt Contacts For Fire Safety Air Conditioners

THINCOL
THINCOLZ4PNH93AFT
3.35 X 2.56 X 4.96 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Thincol33 9.72

Features

It is used to measure the dynamic state of the liquid flowing through the pipeline, such as: water, ethylene, ethylene glycol and other liquids that have no corrosive effect on copper.

When the flow rate of liquid exceeds or falls below the set flow rate, the SPDT contacts can turn on one circuit and cut off the other at the same time. The flow switch is usually used in places requiring interlocking or

Repeatability error is about 2.5%, ensure high stability of products.

IP54 protection level, more safer to use.

Perfect for water treatment system, central air conditioning, water cooling unit.

Liquid Flow Switch, Shuttle, Spdt, 20Va

GEMS SENSORS
ARALL-70460569
3.90 X 2.60 X 5.00 Inches
2.00 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Neobits_ 8.86

Dwyer Flotect Series V6 Mini-Size Flow Switch, Brass Upper And Lower Housing, Dpdt Snap Switch, 1" Npt Process Connection, Brass Tee

DWYER
V6EPB-B-D-3-B
0.01 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Data Alchemy 8.60

Features

Monitor flow in 1/2" to 2" pipe

Explosion-proof

Leak proof lower body machined from bar stock

Weatherproof

Electrical assembly can be easily replaced without removing the unit from the installation so that the process does not have to be shut down

Mcdonnell & Miller on Amazon: A Comprehensive Review

As an online shopper, it's crucial to make informed decisions. This review will focus on Mcdonnell & Miller, a brand that has made its presence felt on Amazon. With its wide range of products in Flow Switches, Mcdonnell & Miller has become a go-to for many shoppers.

Product Range

Mcdonnell & Miller offers a vast product count of 23 items. This diverse selection caters to a wide array of needs and preferences, making it a versatile brand for consumers.

Quality and Pricing

Quality is a defining factor for any brand. Based on customer feedback and ratings, Mcdonnell & Miller's products have an average rating of 5.1 out of 10, indicating a high level of customer satisfaction.

When it comes to pricing, Mcdonnell & Miller has products ranging from a minimum price of $7.45 to a maximum of $614.19, with an average price of $131.05. This pricing structure caters to a wide range of budgets, making Mcdonnell & Miller an accessible choice for many shoppers.

Customer Service

Customer service is the backbone of any successful online brand. Mcdonnell & Miller is sold by neobits_ the portland group voomi supply and maintak, who are known for their commitment to customer satisfaction. They have been responsive and helpful, according to customer reviews and feedback.

Shopping Experience

The shopping experience on Amazon with Mcdonnell & Miller has been largely positive. The brand's wide range of products, combined with the ease of navigation on Amazon, has made shopping a breeze for many customers.

Delivery and Packaging

Delivery and packaging are yet another aspect where Mcdonnell & Miller shines. Items are delivered in a timely manner and the packaging ensures the products reach the customers in pristine condition.

Conclusion

In conclusion, Mcdonnell & Miller offers a wide range of quality products at varying price points, making it a brand worth considering for your next Amazon purchase. Their commitment to customer service, combined with a seamless shopping experience, makes Mcdonnell & Miller stand out in the crowded Amazon marketplace.

Overall Rating

Based on the analysis of product range, quality, pricing, customer service, shopping experience, and delivery, we rate Mcdonnell & Miller [5.1 out of 10 stars].