Check the listing for details. Lot of 4 - UID 2TS / Keystone 4609 - TO-3 Isolated Transistor Component Socket. Condition: Open box. Listed at 12.98 USD. Lot of 4 - UID - 2TS1 / Keystone 4609 - TO-3 Isolated Transistor / Component Socket. Socket is installed onto chassis using eyelets or screws. Transistor is installed afterwards. Assembly and repairs are simplified since socket will stay in place without transistor mounted. white Insulator ensure the component leads are electrically isolated from chassis. Electrically Isolated Power Transistor Socket Status: Discontinued Dimensions: 1.35" x 1.0" X 0.086" Contacts: Brass, Tin Plated Three Solder Terminals, Mounting Holes in each Corner. Tan Phenolic with White Nylon Insulator on Opposite. Identified: "E", "B", "C" on Phenolic Surface. Alternates: Keystone 4609, ECG209, NTE209, Cinch 2TS-1 Applications: Vintage Audio, Amplifiers, Phase Linear & Others Vintage New Old Stock Made In USA Lot of 4