Best Square Flat Washers in 2026

Daisy
Last Updated: Feb 6, 2026

At a Glance: Our Top Picks for Square Flat Washers

800 Pieces 304 Stainless Steel Flat Washers, Fender Washers, Kindroufly 9 Sizes Stainless Steel Washers, Lock Metal Washers Assortment Kit (M2 M2.5 M3 M4 M5 M6 M8 M10 M12)
#TOP1
800 Pieces 304 Stainless Steel Flat Washers, Fender
9.6
PM SCORE
U-Turn - 3/8 Square Beveled Washer Malleable Iron Galvanized (10 Pack)
#TOP2
U-Turn - 3/8 Square Beveled Washer Malleable Iron
8.7
PM SCORE
Hard-to-Find Fastener 014973151881 Square Washers, 1/2 x 2x2 x 3/16, Piece-25
#TOP3
Hard-To-Find Fastener 014973151881 Square Washers, 1/2 X 2X2
8.0
PM SCORE

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Summary of the Best Square Flat Washers of 2026

800 Pieces 304 Stainless Steel Flat Washers, Fender Washers, Kindroufly 9 Sizes Stainless Steel Washers, Lock Metal Washers Assortment Kit (M2 M2.5 M3 M4 M5 M6 M8 M10 M12)

KINDROUFLY
KINDROUFLY---FLAT---WASHER
5.20 X 3.60 X 0.72 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
KINDROUFLY 9.88

Features

√【Kindroufly Combination】: M2 (200 pieces), M2.5 (200 pieces), M3 (100 pieces), M4 (100 pieces), M5 (72 pieces), M6 (50 pieces), M8 (50 pieces), M10 (20 pieces), M12 (8 pieces), total 9 sizes 800pieces, different sizes and enough quantities can meet your different daily needs.

√【High Quality Stainless】: Kindroufly fender washers are made of 304 stainless steel, which have smooth surface, high strength, not easy to deform, corrosion resistance and rust resistance, can ensure a long time using in bad environment like high temperature, cold weather, and high humidity areas.

√【Fender Washers Function】: Flat washers are commonly used to prevent nuts from loosening. Our flat washers are well made, with smooth and shiny surface, highly compatible with screws, nuts and bolts of same sizes and feature solid bearing surface to prevent nut/bolt head from tearing through material.

√【Multi-functional Storage Box】: All Kindroufly 800 pieces 9 sizes stainless steel flat washers are packed in a solid transparent storage box. we put 9 sizes flat washers in 10 grids , each size are marked with a clear label. It is very convenient for you to choose size, easy to carry and store, which can save your time and energy.

√【Widely Applications】: Kindroufly 9 sizes stainless steel washers, lock metal washers, fender washers assortment kit are widely used for interior decoration, outdoor construction, electrical maintenance and furniture repair. If you have any questions about our products, welcome your inquiry and we will solve the problem for you in time.

U-Turn - 3/8 Square Beveled Washer Malleable Iron Galvanized (10 Pack)

U-TURN FASTENERS, INC.
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
U-Turn Fasteners, Inc 9.61

Features

ITEM TYPE - Square Bevled Washer

MATERIAL - Malleable Iron, Galvanized

Hard-To-Find Fastener 014973151881 Square Washers, 1/2 X 2X2 X 3/16, Piece-25

HARD-TO-FIND FASTENER
SQRWSR-126-25
4.13 X 3.25 X 3.25 Inches
3.62 Pounds
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Amazon.com 9.68

Features

Diameter 1: 1/2 inch

Diameter 2: 2 inches

Length: 2 inches

Thickness: 3/16 inches

Material: Steel

45 Mm Plastic Washers Load Spreading Polypropylene Washers For Fixing And Supporting Rigid Foam Insulation Foam Board Load Spreading For Screws Nail(800)

TAIYIN
OJ-2210-M
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
LuTomorro 9.90

Features

Reliable Material: these washers are made of polypropylene, a plastic material, featuring with good insulation, low profile and good durability, which are easy to hold

Size Information: the plastic washers are about 45 mm/ 1.77 inch in diameter, and the middle hole is about 5 mm; Each plastic washer is about 1.7 g

Sufficient to Use: you will get 800 washers for screws and nails, enough for your daily replacement and use in foam board insulation and other repair

Fixing and Supporting: these plastic washers are designed to use for fixing and supporting expanded polystyrene sheets, extruded polystyrene and many types of foam boards

Easy to Install: the round washer is easy to fix with screw or nail, and also you can remove it easily; The extra washers can be stored for the next time to use

#TOP5

Dreneco 3Pcs M12 Square Washers, Stainless Steel Heavy Duty Square Oblique Gasket, I-Steel Flat Gasket For Channel Steel, Missing Angle Washer,

DRENECO
S101N101004
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Dreneco 5.13

Features

Material: Durable 304 stainless steel.Compared with normal stainless steel,it's safer, more durable,non-toxic and corrosion resistant.It is of high hardness and not easy to deform.It can be used in outdoor humid environment.

Fastener Type: Bevel Washer

Features: Bevel washer can Resist loosening caused by vibration and corrosion.Helps to distribute loads of bolts, screws and nuts uniformly.

Usage: Intended for the general use under the head of a bolt or nut.Widely used in slot section.

Wide Application: Square Oblique Washer can be used for many industries and for many different exterior applications.Often used in timber construction, since they develop more friction when tightened against wood. They are also suitable for a variety of applications where a heavy washer is required.

20 Pcs Square Washers Plate ⅝"(Id) X1⅝"X1⅝"X3/16", Hot-Dipped Galvanized Steel Thickness 2.8Mm Heavy Duty Bearing Plate Square Strut Channel Washer For Cold Formed Steel Light Gauge Steel Framing

GBGS
DP02-T20
1.57 X 1.57 X 0.11 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Worldtrend 9.87

Features

20 Pcs Square Washers Plate, Material: Carbon steel Q345 , surface hot-dip galvanized (good impact resistance, wear resistance, corrosion resistance).

Length: 1⅝ inches (40 mm), Width: 1⅝ inches (40 mm) ,Thickness: 2.8mm

Hole Diameter : ⅝ inches(Φ16.8mm )

Square Washers Plate used in light steel frame housing fittings, construction sites, machinery and industrial equipment and other related scenes, and their applications in many areas

Suprwin M12 304 Stainless Steel Square Plate Washers Set, Fastener Hardware Flat Pad Spacer Gasket Square Nut, 1/2"(Id) * 2" *2"(Od) *1/8"(Thk) (M12-50Pcs, Square)

SUPRWIN
SP-1
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Suprwin 9.39

Features

【Solid STAINLESS STEEL】Made of high quality stainless Steel. Made of corrosion resistant metals, has good corrosion resistance, heat resistance, low temperature strength, making it last longer than other hardware on the market today.

【MULTIPLE Purpose】Square plate washers are often used in timber construction since they develop more friction when tightened against wood. They are also suitable for a variety of applications where a heavy washer is required. It can be used on multiple platforms and facets. Designed to be used in conjunction with carriage bolts for the securing of roof trusses but can also be used in a variety of ways on many different projects

【Package】Inside Diameter: 1/2" | Outside Diameter: 2"*2" | Thickness:1/8"" | Quantity: 50pcs | Material: Stainless Steel.

【Widely Application】 Our hardware is very strong and is great for both indoor and outdoor use. The stainless steel is superior to regular steel and provides excellent rust resistance in water applications.

【LIFETIME WARRANTY】 - 100% Satisfaction Guarantee: If you have any problems we will replace them free of charge or issue a full refund! We are so confident that our product is the best on the market that we offer a NO HASSLE LIFETIME GUARANTEE.

10 Pcs Carbon Steel Strut Channel Saddle Washer, 1-5/8" Square Washer Plate C Channel Connector, 4.4Mm Thickness Washer Plate Fastener Hardware, Bolt Not Included

YIDU69Q
ZX12-T10
2.17 X 1.57 X 0.43 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Yilihandu 8.57

Features

Material: carbon steel Q235B, Surface treatment: electrogalvanized,good impact resistance, wear resistance, corrosion resistance.

Product Size:55x40x11.3mm, Thickness: 4.4mm,Hole diameter (1 pcs): φ12.7mm (½ inches)

Fit with steel channel width: 41mm (1⅝ inches)

Application: Saddle washer plate used in strut channel, construction sites, machinery and industrial equipment and other related scenes, and other areas

Package:10 x Saddle Washer Plate Fastener Hardware(Bolt not Included) .

(400 Pcs) #10X1/2" Sealing Washers 304 Stainless Steel Neoprene Epdm Bonded

WENSILON
00002
0.55 X 0.55 X 0.13 Inches
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
WenSiLong 9.75

Features

Material: Our Sealing Gasket Is Made Of 304 Stainless Steel And Epdm Rubber, Durable And Long Life With Good Rust Resistance, You Do Not Have To Feel Frustrated By Rust

Package Quantity: Our Products Are Strictly Controlled By The Quantity Of Each Package, And Packed In A Strong And Durable Box, You Do Not Have To Worry About Receiving A Broken Package And The Number Of Packages Does Not Match The Actual

Features: The Sealing Washer Is Rubber On One Side And Metal On The Other Side Of The Washer. Suitable For Use In Metal Plates, The Rubber Helps To Solve The Problem Of Vibration Noise, The Gasket Helps To Improve The Friction Of The Screw To Enhance The Sturdiness, They Are Good Helpers For Your Work.

Wide Range Of Applications: Suitable For Use In Self-Drilling Screws, Widely Used In Electrical Equipment, Industrial Machinery, Construction, Etc.

Contact Us: If You Have Any Questions About Our Products, Please Feel Free To Contact Us At Yibian

Wensilon (120Pcs)1/4"X1 Stainless Steel 304 Metal Flat Washers For Screws And Bolts, Suitable For Factory Maintenance, Kitchen, Store And Outdoor Construction

WENSILON
PD0010
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
WenSiLong 9.75

Features

WHAT YOU GET: 100 stainless steel 1/4"x1 flat pads ideal for use in sheet metal and wet environments with very high form corrosion resistance in 304 material

304 MATERIAL: Our pads are made of 304 stainless steel, which is longer lasting than other hardware on the market and will last longer in harsh environments such as high temperature, low temperature and high humidity.

WIDELY USED: Our flat pad can be used to fix bolts with diameter smaller than the hole of the washer, suitable for general industry such as indoor decoration, outdoor construction, electrical repair and furniture repair.

PRODUCT FUNCTION: Our flat washers are used to distribute the load of threaded bolts, screws and nuts, providing a smooth load bearing surface

SIZE: Inner diameter 0.27in Outer diameter 1in Thickness 0.06in

Wensilon (600Pcs)1/4" Stainless Steel 304 Metal Stainless Lock Washers For Screws And Bolts, Suitable For Factory Maintenance, Kitchen, Store And Outdoor Construction

WENSILON
DHDQ002
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
WenSiLong 9.75

Features

WHAT YOU GET: 100 stainless steel #8x3/8" Spring Lock Washers ideal for use in sheet metal and wet environments with very high form corrosion resistance in 304 material

304 MATERIAL: Our Spring Lock Washers are made of 304 stainless steel, which is longer lasting than other hardware on the market and will last longer in harsh environments such as high temperature, low temperature and high humidity.

WIDELY USED: Our Spring Lock Washers can be used to fix bolts with diameter smaller than the hole of the washer, suitable for general industry such as indoor decoration, outdoor construction, electrical repair and furniture repair.

PRODUCT FUNCTION: Our Spring Lock Washers are used to distribute the load of threaded bolts, screws and nuts, providing a smooth load bearing surface

SIZE: Inner diameter 0.475in Outer diameter 0.295in Thickness 0.07in

Uxcell Square Washer, 20Pcs M4X20X20X1Mm 304 Stainless Steel Square Plate Washers Flat Pad Spacer Gasket For Hardware Fastener

UXCELL
A23032200UX0490
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Amadeo City 9.87

Features

Product Name: Square Washer; Fit Screw/Bolt Thread Diameter: M4(#8); Inside Diameter: 4.5mm / 0.18"; Outside Size: 20 x 20 x 1mm / 0.79" x 0.79" x 0.04"(L*W*T); Package Content: 20pcs x Square Washers

Material: Square plate washers are made of 304 stainless steel, rust and corrosion-resistant, with good heat and low temperature strength, suitable for indoor and outdoor use.

Advantages: Square washers provide more contact area for fasteners, it is a good choice for applications requiring higher carrying capacity, provide greater stability and prevent loosening.

Application: Square washers fit into slots and channels and have flat sides to keep them from rotating, commonly used in mechanical equipment and wood construction, where they create more friction when tightening the wood and are used to fix bolts, screws and other fasteners. Such as use with carriage bolts to secure roof trusses. Widely used in construction, plumbing, electrical, automotive and other industries, etc.

Note: When purchasing a square washer, you need to determine the correct size, thickness, and material for your intended application. These factors can greatly affect the performance and durability of the washer.

Uxcell Square Washer, 2Pcs M12X40X40X4Mm 304 Stainless Steel Square Plate Washers Flat Pad Spacer Gasket For Hardware Fastener

UXCELL
A23032200UX0514
SELLER SELLER SCORE AMAZON FULFILLED PRIME FREE SHIPPING
Amadeo City 9.87

Features

Product Name: Square Washer; Fit Screw/Bolt Thread Diameter: M3(#5); Inside Diameter: 13.2mm / 0.52"; Outside Size: 40 x 40 x 4mm / 1.57" x 1.57" x 0.16"(L*W*T); Package Content: 2pcs x Square Washers

Material: Square plate washers are made of 304 stainless steel, rust and corrosion-resistant, with good heat and low temperature strength, suitable for indoor and outdoor use.

Advantages: Square washers provide more contact area for fasteners, it is a good choice for applications requiring higher carrying capacity, provide greater stability and prevent loosening.

Application: Square washers fit into slots and channels and have flat sides to keep them from rotating, commonly used in mechanical equipment and wood construction, where they create more friction when tightening the wood and are used to fix bolts, screws and other fasteners. Such as use with carriage bolts to secure roof trusses. Widely used in construction, plumbing, electrical, automotive and other industries, etc.

Note: When purchasing a square washer, you need to determine the correct size, thickness, and material for your intended application. These factors can greatly affect the performance and durability of the washer.

Top 10 flat washers square Brands on Amazon

Here is the list of top-rated brands that were evaluated by PM.

Brand Count
Wensilon 3
Uxcell 2
Dreneco 1
Gbgs 1
Hard-To-Find Fastener 1
Kindroufly 1
Suprwin 1
Taiyin 1
U-Turn Fasteners, Inc. 1
Yidu69Q 1

Top 10 flat washers square Brands Pie Chart


We've carried out a comprehensive analysis of 423 reviews on flat washers square, using our selection criteria to identify the best options in the categories. Our findings reveal that most customers typically select flat washers square priced around $18.09, with top brands including and

Our team of expert editors reviewed these high-quality items and handpicked the top 13 flat washers square for your consideration. We've also done extensive research on numerous sellers, identifying the best ones in the categories category. These include and .

We are dedicated to assisting our users in finding the right washers Products based on their needs, saving them considerable time when choosing which flat washers square to buy. We take pride in the number of satisfied users we've helped through our thorough and insightful reviews.