New item 7/6/17! Piston ring set for standard (3-1/4") bore Onan B43M and B48M engines used on the Case/Ingersoll 226, 446, 448 and 648 tractors. This kit services one piston, order two for a complete rebuild. Replaces J I Case and Ingersoll part number C29739 as well as the earlier Onan part number 113-0189. Please note, this part has been discontinued by Onan and we have a limited number in stock. No backorders on this item.