The washers I took off my heads (Type 4) 30 years ago got mixed in with my other hardware. I fished out 16 M10 washers that fit, but want to make sure I'm installing correct washers and maybe source some new ones if needed. PET just lists:
washer
A 10,5
Are they special thickness or hardness etc.?
BTW, anyone know what the "A", "B", etc. for hardware specs in the PET mean? I haven't been able to find a key. Must be looking in the wrong place.