BT13 Series Galvanised 18 Gauge Brad Nails & Fuel.
To Suit GBT1850K Cordless Gas Bran Nailer

Finish nails (Brads) and T nails are normally of a rectangular cross section instead of being round.

Their diameters are less than the coil and stick nails, and are primarily used for finish and trim work in the construction and joinery industries. Finish Nails and Brads have heads that are rectangular. They are the same width as the shank, but the breadth of them is greater than the shank. This ensures that their holding power is enhanced, but of course the pull through force is lower than for nails with larger, Round or Clipped Heads.