Compatibility: This recoil pull starter rewind is designed to be compatible with a range of models including bg86, bg86c, bg56, bg56c, sh86. When the pull rope is pulled into the correct position, the recoil pull starter and the drive plate on the machine will automatically aligned, At this point, the recoil pull starter fits snugly into the engine, you will feel that the pull rope can be pulled more smoothly.