Polished nickel completeturn knobOFF/ONsolid brass socket, shell, cap to wire your lamps. The cap (with set screw)has 3/8" threaded hole to screw onto standard 1/8 IPSsteel pipe. It has 2 terminals. Rated 250W, 250V. It is stamped "made in China". These work with "standard" or "medium-based" light bulbs.We combine with other items to save freight. $6.68 each.Shipping is $2.80 plus $.34 for each additional socket.Combined shipping- to get cheapest shipping costs (when buying different items)please buy what you need (WITHOUT SHOPPING CART) and “request invoice” (BEFORE YOU PAY)so we can send invoice with lower shipping costs.SHOPPING CART DOES NOT SEEM TO WORK FOR COMBINED SHIPPING.