Original OEM (original equipment manufacturer) type 4 lug AC power switch. This version has tabs that attaches to the rear housing of the volume control of Fisher 400, 500 and 800 series tube type Am-FM receivers. You must remove and disassemble the control to install this version of switch. Please note there is another version that removes easily, this is NOT THAT VERSION . Be SURE to look carefully at the pictures to see this version. This part is NOS and has never been used. We sell and repair most any control 1930-1970 era. Antique Audio Plymouth , Michigan. We’ll be at the Vintage Electronics Expo /  Kalamazoo Hamfest Saturday, Oct 5 2024 9am-4pm.   Google Kalamazoo Hamfest for info