McMaster 91812A724 Extreme Vibration Resistant Wedge Lock Washer, 316 Stainless Steel, for M20 Screw Size, 0.840" ID, 1.210" OD 70497 Exterior Depth 32 in Exterior Depth 32 in Box Ends Incorporate the TorquePlus(TM) system Offset 15 Degrees Wrench Item Box End Wrench Box End Style Spline Ratcheting Configuration Non Ratcheting Insulated No Reversing No Tether Capable Tether Capable Wrench Shape Half Moon Head Movement Fixed Wrench Product Grouping Wrenches Wrench Material Steel Single End Double End Double End Nonsparking No Grip Style Plain Non Magnetic No Handle Type Steel Corrosion Resistant Yes Head Offset Angle 15 Degrees Ratcheting No Measurement Type SAE Tether Style Not Tether Capable Box End Type 12 Point Box End Weight 0 salt water these washers won't degrade when exposed to harsh weather