Includes (4) 458 Spark Plugs. Thread Size: 14mm, Thread Pitch: 1.25mm, Seat Type: Gasket, Reach: 9.5mm (3/8"). Hex Size: 13/16" (21mm), Terminal Type: Solid. Material: Nickel, Type: Standard, Projection: Non-Projected. Copper core improves resistance to fouling. Compatible with the Following: Bosch: 7538, 7801, W12E, W45T3, W9EC0, WR11E0, WR9EC, Champion: 5861, 861, 868, 947, J19LM, QJ19LM, RJ12C, RJ19LM, RJ19LM4, NGK: 1147, 3110, 3410, 3841, 4146, 4861, 4864, 5798, 741, 7931, B2, B2LM, B2LMY, BR2LM, CS1