Functions: This assembly kit can soonly replace you old trigger valve and pluger valve, you can replace any parts of it or the assembly, it controls the air flow and the firing of the nails. Pluger (A) is the main part of the power tool, safety plunger (B) is the secondary part that prevents accidental firing when the trigger is not pressed.
Warranty: Returnable for 6 Months and Changeable for 1 Year(return and change for free)