The Blue Spot 21mm 1/2" Impact scaffold socket is manufactured from chrome molybdenum for increased durability, with a blackened phosphate coating which protects against corrosion. 52mm deep and lighter than a regular deep socket, it is the most common socket used by scaffolders. The socket has a safety pin and ring which keeps the socket secure and in place on the impact driver, making it the ideal socket to be used at heights. Manufactured from chrome molybdenum for increased durability Use with 1/2" Impact drivers.