Speed Systems' Ratcheting Box Wrenches are designed to provide end to end isolation for maximum safety. The RBW wrenches have an ergonomically designed handle with a center "window" displaying the separation of the tool ends. Features: 5/16" hex shaft extended, 1-1/2" on one side Thick-walled plastic ergonomic handle with center isolation hole Rated 1000V Hex shaft for use on secondary set screw bar connectors Click HERE for all Speed Systems insulated wrenches. Speed Systems 1000V Insulated Ratcheting 5/16" Single Hex Shaft Wrench RBW-1