The NV50AP3 holds 350 caps and nails. Unit can fasten plastic and steel caps making it a more flexible tool. Unit has an integrated FlipFire switch that lets you switch from sequential to ''bump'' fire. Tool-less depth drive adjustment and adjustable exhausts make this the ideal tool for Tyvek, insulation, tar paper and any other sheathing. Unit weighs only 5.5 lbs. 5 year professional warranty