Lincoln K and KP Numbers › Lincoln Electric KP4745-M 9/20 MEDIUM BACK CAP Lincoln Electric KP4745-M 9/20 MEDIUM BACK CAP Sale Price: $18.95 Original Price: $21.22 9/20 MEDIUM BACK CAP PURCHASE PRICE SHOWN IS FOR A QUANTITY OF 2.000 Add To Cart Added! 9/20 MEDIUM BACK CAP PURCHASE PRICE SHOWN IS FOR A QUANTITY OF 2.000