Spark Plug Deep Socket Set 2pce 3 8 inch Overview Hardened tempered chrome plated corrosion resistant chrome vanadium. Chamfered end for positive nut location, with rubber inserts for plug retention and protection. Contents: 16 and 21mm spark plug sockets." name="description"/> Spark Plug Deep Socket Set 2pce 3 8 inch Overview Hardened tempered chrome plated corrosion resistant chrome vanadium. Chamfered end for positive nut location, with rubber inserts for plug retention and protection. Contents: 16 and 21mm spark plug sockets." property="og:description"/> Spark Plug Deep Socket Set 2pce 3 8 inch Overview Hardened tempered chrome plated corrosion resistant chrome vanadium. Chamfered end for positive nut location, with rubber inserts for plug retention and protection. Contents: 16 and 21mm spark plug sockets." name="twitter:description"/>