Genuine Belton nine-pin tube socket for 12AX7, 12AT7, etc. Brown phenolic plastic body, tinned solder lug contacts, mounts from top of chassis, standard sized mounting centers 1.097", J-slot collar for standard sized tube shields. Fits through a hole in your chassis slightly larger than .725". Belton makes some of the nicest modern conventional tube sockets, similar in my view to the old USA Cinch and British McMurdo.