The Bostitch P4 is another fine stapler design by J.F. Cavanagh. Perhaps you remember the Bostitch P1 stapler featured May, 24, 2008. The P4 has the look of a staple gun tacker but Cavanagh included an anvil plate with a very deep throat. The combination of increased staple-driving leverage and the extended reach of the anvil plate suggests it was designed for commercial or industrial use. In my opinion, at the time the P4 and the P1 were two of the more innovative stapler designs offered by Bostitch. They took the power of a tacker and applied it for stapling good, not evil.Excerpt from the Stapler of the Week, March, 30, 2009.