Schuco handles

Last week I was called to a reasonably new flat in Grays Essex,the tenant had lost the key to one of the tilt and open windows.i took some photos of the handle and made sone enquiries,I informed the tenant of the price and he gave me the go ahead.I orderd the handle in which took a couple of days to arrive. Rang the tenant who asked me to fit it today,I picked the lock  open removed the old handle and fitted the new one,the tenant can bow open,close and lock the window