B8S 3810 NGK Spark Plug for vintage Evinrude/Johnson, Sears, and Wizard outboards. Also fits some Pioneer & Craftsman chain saws and Pioneer generators.

Equivalent to Mercury Marine 33-813415; OMC 509564, 765959; Yamaha NGK-B8S00-00-00; Champion J4C.

Thread diameter: 14mm
Thread pitch: 1.25mm
Seat type: gasket
Reach: 9.5mm (3/8")
Hex size: 13/16" (21mm)
Terminal type: removable nut
Gap: .028" (0.7mm)
Resistor: no

Please check the part numbers for your specific fitment needs.

cat-E41