JOHN DEERE: Ring set for 3 ring piston, 1 used per engine. For 219 CID 4 cylinder, diesel engine serial number 101360 to 211699. 4.02 standard bore; keystone top compression ring. JOHN DEERE: Piston Ring Set, 4.02 inch bore. 1 at 1/8 inch keystone, 1 at 3/32 inch, 1 at .196 inch