I think VXB may well be sourcing from China now. I think, but can't be sure, that the last one I sourced from them did have the P/N on it but that was some years ago. It seems that if all the parts are in good shape with a good starter and electrical system the E-start works just fine. I know that just replacing the sprag with the beat up parts didn't last. I suspect that the original parts weren't up to snuff - not hard enough and/or not in tolerance allowing the sprags to roll and lock.