SEMS Screw – Hex Head

SEMS screws (Screw and washer pre-assembled units) are hex head screws with captive washers permanently retained under the head. The washer — flat, spring, or combination — is captured on the shank during manufacture and cannot fall off or be misplaced during assembly. This pre-assembled design significantly speeds up production line assembly, eliminates the risk of missing or misaligned washers, and reduces component inventory. Widely used in automotive assembly, consumer electronics, electrical panel assembly, and any high-volume manufacturing environment where assembly efficiency and torque consistency are critical. Available with flat washers for load distribution or spring washers for vibration resistance.