Specification:
1. Thread diameter: 13.8 mm, hex size: 16 mm, spark plug length: 49 mm
2. Compatible with Models: Troy-Bilt: TB22EC, TB80EC, TB2BP, TB32EC, TB32EC, TB32EC, 
YM21CS, TB2044XP, TB2040XP, TB225, TB21EC
3. Bolens: BL110, 41BD110G965, 41BD160G965, BL160, BL160, BL425-21AK125G965
4. MTD: 41AD251G900, 41AD260G900, 41AD160G965, MS2550
Yard M: YM71SS, YM2BP, YM2BV
5. For small engines such as string trimmers, tillers, blowers, etc.