Spark Plug Socket Hand Chrome 6-Point Socket Size 18 mm Bolt Clearance 8.4mm Drive Size 3/8 in Impact Rated No Chrome Vanadium Steel Metric Non-Magnetic No Non-Sparking No Socket Depth Deep ASME B107.17 ASME B107.34 ASME B107.4 ASTM B117 ASTM B571 ASTM D968-05 No