Piston Kit W Ring For Yanmar Engine John Deere Tractor Excavator Loader 4TNE78. 4pcs Piston, STD size. 4set Piston Ring Set For 4pistons. International Buyers – Please Note. If you need to receive the goods. If you are not satisfied with the item, you can return it, except for any installed parts. Please send item back in original package (new and un-used, accessories included).