Designed to Compensate for Length Changes Due to Temperature Variations in Exposed Conduit Runs | For Use With Non-Metallic Sheathed Cable | For Use With Threaded Rigid Metal Conduit and Imc | Hex-Key Ends Are Square-Cut for a Secure Full-Depth Fit and Maximum Contact With the Hex Socket to Prevent Slippage and Stripping of the SocketFurbay Electric Supp