Autolite Genuine Small Engine Copper Core Spark Plug # 66

Genuine Autolite replacement part. Thread Size: 14mm, Thread Pitch: 1.25mm, Seat Type: Gasket, Reach: 19mm (3/4"). Hex Size: 13/16" (21mm), Terminal Type: Removable Nut. Material: Nickel, Type: Standard, Projection: Projected. Copper core improves resistance to fouling.