$42.00
Part 257420 is a 10-pack of carbide balls for the Graco Fusion AP and Fusion PC spray guns. Graco's parts list gives it as a ball, carbide, package of 10, and it is catalogued as a check ball accessory kit.
On the gun parts diagram the item is called out simply as "Carbide ball". If you are rebuilding a check valve, confirm from your exploded view that the ball is what you need, and check whether the check valve kit you are already ordering covers it.
Buying the 10-pack means spares stay in the toolbox rather than one ball at a time. Genuine Graco OEM part 257420.
