The 21 Full Round Head 3-1/2 In. Framing Nailer (model AN924) combines durable construction and robust performance with ease-of-use features for wood framing applications. 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. It is ideal for framers, roofers and carpenters. The AN924 drives 21 plastic collated framing nails from 2 In. to 3 1/2 In. in length and 0.113 to 0.148 In. diameter. It has a 2-mode selector switch (bump, sequential) for increased convenience. The AN924 has a lightweight design (only 8.3 Lb.) with durability features that include a heat-treated S7 steel driver blade, a solid aluminum top-loading magazine, and a nail lock-out mechanism that protects the tool and work surface from dry-fires. Added features include tool-less depth adjustment for flush or countersink nailing, added tool hook, and an ergonomic rubberized grip.