Lincoln K and KP Numbers › Lincoln Electric KP5129-2 DIFFUSER, SLIP-ON, 550A Lincoln Electric KP5129-2 DIFFUSER, SLIP-ON, 550A Sale Price: $13.63 Original Price: $15.26 DIFFUSER, SLIP-ON, 550A PURCHASE PRICE SHOWN IS FOR A QUANTITY OF 1.000 Add To Cart Added! DIFFUSER, SLIP-ON, 550A PURCHASE PRICE SHOWN IS FOR A QUANTITY OF 1.000