Keep your Makita® 21° Full Round Head 3-1/2” Framing Nailer (AN924, sold separately) operating at optimum efficiency with the comprehensive replacement kit. The Trigger Valve Assembly Kit (HY00000959) contains the parts needed for replacing the trigger valve. Each part is made of high quality materials for long lasting performance. The AN924 is engineered for a range of applications including framing walls, floors and roofs, as well as construction of roof and floor decking, floor and wall sheathing/siding, and sub-flooring.