Value Collection SIWIS0370USA-100BX Lock Washer 100

Product Description

The VALUE COLLECTION SIWIS0370USA-100BX is a zinc-plated, Grade 2 steel internal tooth lock washer designed for 3/8 inch screws. It features a 0.398 inch inside diameter and a 0.692 inch outside diameter, with a thickness of 0.04 inches. The internal tooth pattern bites into the mating surface and fastener head to resist loosening caused by vibration and torque. This washer is a standard hardware component installed by electricians, plumbers, HVAC technicians, and general contractors in a wide range of mechanical and structural assemblies. Sold in a minimum order quantity of 100 units per box.

Internal tooth lock washers in this size range are used in residential and light commercial applications wherever a standard 3/8 inch fastener requires vibration resistance. Common install scenarios include electrical panel work, equipment mounting, conduit supports, HVAC equipment brackets, and general sheet-metal assemblies. The zinc plating provides moderate corrosion resistance suitable for indoor and protected outdoor environments. Grade 2 steel construction meets typical mechanical fastening requirements across most trade applications.

Key Features

• Internal tooth design grips mating surfaces to resist loosening under vibration
• 0.398 inch inside diameter fits standard 3/8 inch fasteners
• 0.692 inch outside diameter with 0.04 inch thickness
• Zinc-plated finish provides moderate corrosion resistance
• Grade 2 steel construction for general mechanical fastening duty
• Sold in a box of 100 for job-site and shop use

Compatibility

Designed as a standard internal tooth lock washer for use with 3/8 inch screws and bolts across general mechanical, electrical, and HVAC fastening applications.

Installation Notes

Install with the teeth facing the fastener head or the mating surface to ensure proper grip and vibration resistance. Place the washer before tightening the fastener to final torque — do not reuse a washer that has been fully compressed. Follow applicable NEC, IPC, or IFGC guidelines when using fasteners in code-governed assemblies. No special tools are required for installation beyond standard hand or power drivers.