This is a genuine Mountfield Woodruff Key p/n 112139100, Which can be used on the Mountfield HP470, 420HP, 470HP, 470SP 550SP Combi, mowers & 1228H, 1228M, 1436H, 1436M ride-On. It also fits Castel Garden J92, J92H, EL63 Ride-on If you are unsure whether this is the correct part for your machine, please fill out our online parts enquiry form here. The technical department will then respond to confirm whether or not it is the correct part for your machine.