Value Collection SEWCIS0310USA-100BX Lock Washer 100pk

Product Description

The VALUE COLLECTION SEWCIS0310USA-100BX is a zinc-plated, external tooth lock washer manufactured from Grade 2 steel. Designed for use with 5/16 inch screws, this washer features an inside diameter of 0.333 inches and an outside diameter of 0.599 inches, with a thickness of 0.028 inches. The external tooth design bites into the mating surface and fastener head to resist loosening caused by vibration and torque. This box contains 100 washers. Electricians, plumbers, HVAC technicians, and general contractors use external tooth lock washers in panel assembly, equipment mounting, and structural fastening applications where joint integrity under vibration is required.

This washer is suited for light-duty to medium-duty fastening in residential and commercial applications. The zinc plating provides corrosion resistance for use in indoor environments and sheltered outdoor assemblies. External tooth lock washers of this size are commonly installed in electrical enclosures, HVAC equipment cabinets, junction boxes, and mechanical assemblies where a standard 5/16 inch fastener is used. The countersunk feature accommodates flush-mount or countersunk fastener configurations. Installation is typically performed by licensed electricians, HVAC technicians, plumbers, or mechanical contractors as part of routine equipment assembly or repair.

Key Features

• External tooth design resists loosening under vibration and dynamic loads
• Zinc-plated finish provides corrosion resistance for indoor and sheltered applications
• Grade 2 steel construction for light-duty to medium-duty fastening
• Countersunk feature supports flush or countersunk fastener installations
• Inside diameter of 0.333 inches fits standard 5/16 inch screws
• Sold in a box of 100 washers for job-site or shop stocking

Compatibility

Designed for use with 5/16 inch screws and bolts in standard fastening applications requiring an external tooth lock washer.

Installation Notes

Install external tooth lock washers between the fastener head and the mating surface, with the teeth facing the fastener head. Do not reuse lock washers that have been fully compressed, as the teeth lose their locking effectiveness. Ensure the mating surfaces are clean and free of debris before assembly. Follow applicable mechanical and electrical codes, including NEC requirements where lock washers are used in electrical enclosure assemblies.