The NR83A5 full round head framing nailer with depth adjustment is used for floor and wall framing, truss build-up, window build-up, construction of subflooring and roof decking, wall sheathing and mobile home and modular home construction. The NR83A5 is like the original NR83A that you have come to trust, but now with an improved trigger design and sharing all the same internal parts as the original NR83A .The NR83A5 relies on the same cylinder valve drive system as the NR83A, which offers both rapid response and great driving power.