21mm Spark Plug Socket - 1/2" Square Drive - Car Engine Maintenance Nut Tool Overview: cold-forged Chrome Vanadium steel socket. Hardened, tempered and chrome plated. Fully polished mirror finish with knurled ring. Socket insert grips ceramic insulation and assists in extraction of plug. Especially useful on deep-seated plugs. For other variations of individual Spark Plug Sockets, see page XXX. Features: Cold-forged Chrome Vanadium steel socket. Hardened, tempered and chrome plated. Fully polished mirror finish with knurled ring Socket insert grips ceramic insulation and assists in extraction of plug. Especially useful on deep-seated plugs. Lifetime guarantee*. Specification: Drive - 1/2"Sq Material - Chrome Vanadium Net Weight - 0.14kg Size - 21mm Further Information: We sell a wide variety of tools & workshop equipment for both the DIY and Professional markets. With well over 10,000 lines of equipment suiting all jobs big or small, our online store has it all. If you can’t quite