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18-8 Stainless Steel Unthreaded Spacers
18-8 stainless steel spacers have good corrosion resistance and may be mildly magnetic.
For technical drawings and 3-D models, click on a part number.
Metric General Purpose Washers
Use these metric washers to evenly distribute the load under bolt or screw heads and nuts when fastening. They can also act as spacers.
Stainless steel washers are more corrosion resistant than steel washers, and almost as strong. 18-8 and 17-7 PH stainless steel washers will hold up in humid, damp, and washdown environments, but will corrode if exposed to salt water or chemicals. 17-7 PH stainless steel washers are stronger than 18-8 stainless steel. Black-oxide 18-8 stainless steel washers have a matte-black finish. More corrosion resistant than 18-8 and 17-7 PH stainless steel, 316 stainless steel washers will not corrode from salt water, chlorine solutions, and chemicals.
Steel washers are stronger and more wear resistant than stainless steel washers. Zinc- and zinc yellow-chromate plated steel washers have an outer layer of zinc that protects the inner steel from rust and extends the life of the washer. Although they are stronger and more wear resistant than stainless steel, they are not as corrosion resistant. Use them in wet environments, but avoid contact with salt water and chemicals. At one-third the weight of steel, aluminum washers are the lightest option. They will not rust in wet environments.
Washers that meet ISO 7089, 7090, 7091, and 7092 (formerly DIN 125, 126, and 433), meet international standards for fastener dimensions. The ISO 7091 washers have a slightly rougher surface than a typical flat washer.
For technical drawings and 3-D models, click on a part number.
| For Screw Size  | ID, mm | OD, mm | Thickness, mm | Hardness | Specifications Met | Pkg. Qty. | Pkg. | |
18-8 Stainless Steel | ||||||||
|---|---|---|---|---|---|---|---|---|
| M3.5 | 3.7 | 7.0 | 0.5-0.6 | Rockwell B75 | DIN 433 | 100 | 000000000 | 00000 |
| M3.5 | 3.7 | 8.0 | 0.4-0.6 | Not Rated | DIN 125; ISO 7089 | 100 | 000000000 | 0000 |
Black-Oxide 18-8 Stainless Steel | ||||||||
| M3.5 | 3.7 | 8.0 | 0.5-0.6 | Rockwell B75 | DIN 125 | 100 | 000000000 | 00000 |
316 Stainless Steel | ||||||||
| M3.5 | 3.7 | 8.0 | 0.4-0.6 | Not Rated | DIN 125; ISO 7089 | 100 | 000000000 | 0000 |
Zinc-Plated Steel | ||||||||
| M3.5 | 3.7 | 7.0 | 0.4-0.6 | Rockwell B76 | DIN 433; ISO 7092 | 100 | 000000000 | 0000 |
| M3.5 | 3.7 | 8.0 | 0.4-0.6 | Rockwell B75 | DIN 125; ISO 7089 | 100 | 000000000 | 0000 |
Aluminum | ||||||||
| M3.5 | 3.7 | 8.0 | 0.4-0.6 | Not Rated | DIN 125; ISO 7089 | 10 | 000000000 | 00000 |
Metric Plastic Washers
These plastic washers are good electrical insulators.
Nylon washers are stronger than polycarbonate and UHMW washers. Exposure to moisture may cause them to expand.
Polycarbonate washers are more rigid than most plastic washers for high impact resistance. They have good moisture resistance and withstand oil, greases, and detergents.
For technical drawings and 3-D models, click on a part number.
Temperature Range, °F | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| For Screw Size | ID, mm | OD, mm | Thick., mm | Min. | Max. | Hardness | Specifications Met | Pkg. Qty. | Pkg. | |
Nylon Plastic | ||||||||||
Black | ||||||||||
| M3.5 | 3.7 | 8.0 | 0.5-0.6 | -40° | 212° | Rockwell R120 | DIN 125 | 10 | 000000000 | 00000 |
Off-White | ||||||||||
| M3.5 | 3.7 | 7.0 | 0.4-0.6 | -40° | 220° | Rockwell R120 | DIN 433 | 25 | 000000000 | 00000 |
| M3.5 | 3.7 | 8.0 | 0.6-1.0 | Not Rated | 220° | Rockwell R105 | __ | 100 | 000000000 | 0000 |
Polycarbonate Plastic | ||||||||||
Clear | ||||||||||
| M3.5 | 3.7 | 8.0 | 0.5-1.1 | Not Rated | 212° | Rockwell R118 | __ | 10 | 000000000 | 0000 |
Metric Chemical-Resistant Plastic Washers
These washers surpass most other plastic washers when it comes to withstanding chemicals, oil, and grease. All are excellent electrical insulators.
PTFE washers withstand high temperatures and have a slippery surface that resists wear in high-friction applications.
PVC washers resist acids and alkalies.
For technical drawings and 3-D models, click on a part number.
Metric Electrical-Insulating Plastic Washers
These washers are excellent electrical insulators.
Phenolic washers have low moisture absorption, so they won’t expand or become brittle over time. Color ranges from red-brown to yellow-brown.
Hard fiber washers are resistant to organic solvents and petroleum-based oils. They meet the dimensional standards of DIN 125, but not all meet the thickness requirement.
For technical drawings and 3-D models, click on a part number.
Metric Water- and Steam-Resistant Plastic Washers
Low moisture absorption and good heat resistance make these washers suitable for wet and harsh environments. All are good electrical insulators.
Delrin® acetal plastic washers combine a slippery, wear-resistant surface with good strength and rigidity.
For technical drawings and 3-D models, click on a part number.
| For Screw Size | ID, mm | OD, mm | Thick., mm | Max. Temperature, °F | Hardness | Color | Pkg. Qty. | Pkg. | |
Delrin® Acetal Plastic | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| M3.5 | 3.7 | 8.0 | 0.4-0.6 | 180° | Rockwell M90 | White | 10 | 000000000 | 000000 |
Self-Retaining Washers
Specially shaped tabs grip your screw shank tightly. All of these washers are good electrical insulators.
Nylon washers are more wear resistant than polyethylene washers. They are not, however, as moisture resistant.
For technical drawings and 3-D models, click on a part number.
Clipped Washers
Clipped to fit where standard washers can't, these won't rotate when you position the flat edge against a flat surface.
18-8 stainless steel washers have good chemical resistance and may be mildly magnetic.
For technical drawings and 3-D models, click on a part number.
| For Screw Size | ID | OD | Clipped Wd. | Thick. | Hardness | Pkg. Qty. | Pkg. | |
18-8 Stainless Steel | ||||||||
|---|---|---|---|---|---|---|---|---|
| M3.5 | 3.700mm | 8.000mm | 6.900mm | 0.400mm-0.600mm | Rockwell B68 | 10 | 000000000 | 000000 |
Belleville Spring Lock Washers for Socket Head Screws
These washers have smaller outside diameters than standard spring lock washers to fit neatly under socket head cap screws. Also known as conical washers, these have a slightly cupped shape that gives them spring-like flexibility to grip tighter than split and tooth lock washers. They minimize loosening from wear, temperature changes, and vibration. Serrations on the top and bottom provide extra gripping power. Load-rated Belleville disc springs are also available.
Zinc-plated steel washers are corrosion resistant in wet environments.
18-8 stainless steel washers have good chemical resistance and may be mildly magnetic.
For technical drawings and 3-D models, click on a part number.
Spring Lock Washers for Plastic Screws
Designed for use with plastic screws, these acetal washers are good electrical insulators. They are excellent for use under water and in rotating assemblies. Their slightly cupped shape gives them spring-like flexibility to grip joints tighter than split and tooth lock washers.
For technical drawings and 3-D models, click on a part number.
Temperature Range, °F | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| For Screw Size | ID | OD | Thick. | Overall Ht. | Min. | Max. | Hardness | Color | Pkg. Qty. | Pkg. | |
Acetal Plastic | |||||||||||
| No. 6, M3.5 | 0.152" | 0.316" | 0.022"-0.032" | 0.045" | -40° | 212° | Rockwell M80 | White | 100 | 0000000 | 000000 |
Metric Spring Lock Washers
The arched shape of these washers presses up against a bolt and down against a nut to prevent loosening from wear, vibration, or temperature changes. Similar to a spring, they flatten out as pressure is applied, helping to absorb shocks. They grip bolts more tightly than split and tooth lock washers. Unlike split lock washers, which can only be tightened in one direction, these washers have a continuous body that can rotate in either direction.
Conical and curved washers are functionally the same, and are often referenced using their DIN specifications. These DIN specifications refer to slight differences in OD and thickness. DIN 137A is the standard for curved spring lock washers; although this is no longer an active standard, it’s still commonly referenced.
Steel washers are stronger and more wear resistant than zinc-plated steel and stainless steel. They are best for dry environments, since moisture will cause them to rust. Zinc-plated washers have an outer layer of zinc that protects the inner steel from rust and extends the life of the washer.
For technical drawings and 3-D models, click on a part number.
| For Screw Size | ID, mm | OD, mm | Thick., mm | Overall Ht., mm | Hardness | Pkg. Qty. | Pkg. | |
Curved—DIN 137A | ||||||||
|---|---|---|---|---|---|---|---|---|
Zinc-Plated Steel | ||||||||
| M3.5 | 3.7 | 7.0 | 0.4 | 1.40 | Rockwell C42 | 100 | 000000000 | 00000 |
Metric Split Lock Washers
As a screw is tightened, these metric washers flatten to add tension to the joint, counteracting fatigue around the joint from small amounts of vibration. This makes them a common choice to prevent fasteners from loosening. However, they resist the least amount of vibration compared to other locking washers. They meet a DIN or ASME standard for split lock washer dimensions.
Standard split lock washers have a left-hand helix that have right-hand threads to prevent loosening. They have uneven split ends that bite into fasteners for a tight grip but won’t work with hardened surfaces. They hold better than curved or wave washers. These washers are not reusable after tightening.
Curved and wave split lock washers can be used with fasteners that have right- or left-hand threads to prevent clockwise and counterclockwise rotation. These washers are reusable—they retain their shape when untightened and will not damage fasteners.
Stainless steel washers resist corrosion better than steel and are nearly as strong. 18-8 stainless steel washers withstand humid, damp, and washdown environments but will corrode when exposed to salt water and other chlorine solutions. 316 stainless steel washers resist corrosion from wet environments as well as salt water, chlorine solutions, and chemicals.
Stronger and more durable than stainless steel, steel washers plated with zinc or galvanized withstand varying degrees of corrosion. Zinc-plated steel and zinc yellow-chromate plated steel washers withstand wet environments. However, they will corrode in salt water and chlorine solutions. The zinc plating temporarily protects against rust, but once it wears off, the steel will rust.
Steel washers are stronger and resist wear better than zinc-plated steel and stainless steel washers. Use them in dry environments.
For technical drawings and 3-D models, click on a part number.
| For Screw Size | ID, mm | OD, mm | Thick., mm | Overall Ht., mm | Hardness | Specifications Met | Pkg. Qty. | Pkg. | |
18-8 Stainless Steel | |||||||||
|---|---|---|---|---|---|---|---|---|---|
Standard | |||||||||
| M3.5 | 3.9 | 6.7 | 0.7-0.9 | __ | Not Rated | DIN 127B | 100 | 000000000 | 00000 |
316 Stainless Steel | |||||||||
Standard | |||||||||
| M3.5 | 3.9 | 6.7 | 0.7-0.9 | __ | Rockwell C35 | DIN 127B | 100 | 000000000 | 0000 |
Zinc-Plated Steel | |||||||||
Standard | |||||||||
| M3.5 | 3.6 | 6.7 | 0.7-0.9 | __ | Rockwell C44 | DIN 127B | 100 | 000000000 | 0000 |
Zinc Yellow-Chromate Plated Steel | |||||||||
Curved | |||||||||
| M3.5 | 3.6 | 6.7 | 0.6 | 1.1 | Rockwell C44 | DIN 128A | 100 | 000000000 | 0000 |
Steel | |||||||||
Standard | |||||||||
| M3.5 | 3.9 | 6.7 | 0.7-0.9 | __ | Rockwell C44 | DIN 127B | 100 | 000000000 | 0000 |
Metric Split Lock Washers for Socket Head Screws
Also known as high-collar lock washers, these metric washers have smaller outside diameters than standard split lock washers to fit neatly under socket head cap screws. As the screw is tightened, these washers flatten to add tension to the joint. They counteract fatigue around the joint from small amounts of vibration, making them a common choice to prevent fasteners from loosening. However, they resist the least amount of vibration compared to other locking washers.
These washers are compatible with fasteners that have right-hand threads to prevent loosening. The uneven split ends bite into fasteners for a tight grip, but they won’t work with hardened surfaces. These washers hold better than curved or wave washers. They are not reusable after tightening.
18-8 stainless steel washers have good chemical resistance and may be mildly magnetic.
For technical drawings and 3-D models, click on a part number.
Wedge Lock Washers
These two-piece washers provide more locking power than split, tooth, and spring lock washers. Wedges on the inside lock the two pieces together, and serrations on the exterior grip surfaces to resist loosening from high vibration and shifting. Washers are reusable.
316 stainless steel washers have excellent resistance to chemicals and salt water. They may be mildly magnetic.
Zinc-flake-coated steel washers are corrosion resistant in wet environments.
316 stainless steel and zinc-flake-coated steel washers are comparable to NORD-LOCK® Series washers.
For technical drawings and 3-D models, click on a part number.
| For Screw Size | ID | OD | Thick. | Washer Type | Hardness | Heat Treatment | Pkg. Qty. | Pkg. | |
316 Stainless Steel | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| No. 6, M3.5 | 0.150" | 0.300" | 0.080"-0.100" | Wedge Lock | Rockwell C51 | Case Hardened | 1 | 000000000 | 00000 |
| No. 6, M3.5 | 0.150" | 0.350" | 0.080"-0.100" | Wedge Lock | Rockwell C51 | Case Hardened | 1 | 000000000 | 0000 |
Zinc-Flake-Coated Steel | |||||||||
| No. 6, M3.5 | 0.150" | 0.300" | 0.060"-0.080" | Wedge Lock | Rockwell C46 | __ | 20 | 000000000 | 00000 |
| No. 6, M3.5 | 0.150" | 0.350" | 0.060"-0.080" | Wedge Lock | Rockwell C46 | __ | 20 | 000000000 | 00000 |
Metric Internal-Tooth Lock Washers
Internal teeth dig into the screw head while the smooth outside edge won't snag objects. These washers provide greater vibration resistance than split lock washers. Use with fasteners that have small heads, such as fillister and cheese head screws.
Zinc-plated steel washers resist corrosion in wet environments.
18-8 stainless steel washers have good chemical resistance and may be mildly magnetic.
For technical drawings and 3-D models, click on a part number.
Metric External-Tooth Lock Washers
Teeth on the outside edge of these washers bite into the screw head and joint for a tight grip. Use with fasteners that have heads large enough to make contact with the teeth, such as pan, button, and binding head screws.
Zinc-plated steel washers are corrosion resistant in wet environments.
18-8 stainless steel washers have good chemical resistance and may be mildly magnetic.
For technical drawings and 3-D models, click on a part number.
Metric Single-Wave Washers
These curved, flexible washers act like springs to compensate for tolerance variations and uneven surfaces. You can also use them to damp vibration.
18-8 stainless steel washers have good chemical resistance and may be mildly magnetic.
For technical drawings and 3-D models, click on a part number.
| For Screw Size | ID, mm | OD, mm | Thick., mm | Overall Ht., mm | Hardness | Specifications Met | Pkg. Qty. | Pkg. | |
18-8 Stainless Steel | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| M3.5 | 3.7 | 8.0 | 0.5 | 1.8 | Not Rated | DIN 137B | 100 | 000000000 | 000000 |