Uneeda Bolt & Screw Co., stocks a variety of washers in different sizes and finishes. Common materials include steel, stainless steel, brass, nylon, aluminum, bronze, brass and copper. ![]() FENDER WASHER: A flat washer, typically having a small inside diameter and very large outside diameter. |
SAE FLAT WASHER: Society of Automotive Engineers (SAE). This washer tends to have a tighter tolerance on the Inside Diameter (ID) and Outside Diameter (OD) than a USS Flat Washer. |
USS FLAT WASHER: United States Standards (USS). USS Flat Washer is also known as a wrought washer. It is the most common washer used on fraction diameter fasteners such as 1/4, 5/16, 3/8 etc. |
![]() MACHINE SCREW WASHER: Tends to have the smallest ID & OD and typically come in number sizes, ie: #4, #6, #8, etc. |
MEDIUM SPLIT LOCK WASHER: Also known as a helical split lock washer. It has a split ring offset spring tension. When tightened, it creates back pressure on the head or nut side of the fastener. This back pressure creates a locking action. |
CUP WASHER: Used under the head of a flat (82 countersink and oval head) to create a countersink on a flat surface. It tends to have an aesthetically pleasing look. |
![]() INTERNAL LOCK WASHER: A lock washer whose teeth are in the inside diameter. |
EXTERNAL LOCK WASHER: Made of spring steel. Has the same properties as the Internal lock washer except the teeth are on the outside diameter. |
INTERNAL/EXTERNAL LOCK WASHER: Made of spring steel. Combines both Internal & External washers together, having teeth on both the inside and outside. |