Thsi kit is for the G-valve on mIneral oil Silver Spirit/Spurs and derivatives.  The seals are made from the correct Nitrile/Buna-N material to withstand mineral oil.  This kit also includes a new stainless insert, hardened stainless ball and bleeder valve with cap.  The old insert is removed with a small easy-out.
These are not for SY RR363 cars.