Lock Washer Lock Washer Type Wedge Lock Finish Delta Protect Material Steel For Screw Size 5/8 in Inside Diameter 0.651 in Outside Diameter 1.247 in Maximum Thickness 0.188 in Assembly Thickness 0.188 in Color Silver Material Grade/Class Case Hardened Pack Size Small Pack Resistance Properties Shock Resistant Vibration Resistant Rockwell Hardness HRC40 System of Measurement Inch Package Quantity 100