Facom 1/2" Drive 1000v Insulated Socket. Sockets should be used with an insulated ratchet/torque wrench, T-handle or other insulated driver/extension (from Facom, Cementex or Salisbury) to ensure adequate protection. This socket (a component of the S.401AVSE set) has been discontinued by Facom....I have 1 left in stock.