Uniframe Construction For Greater Durability. Thumb-Activated Pressure Release Stops Caulking Flow. Powerful Piston Design For Trouble-Free Performance. With Seal Puncture Tool, Spout Cutter And Ladder Hook. No More Hand Tiring Ratcheting. No Mess And No Waste. Recommended For All Grades Of Caulks, Sealants And Adhesives From Heavy To Light Consistencies. 10:1 Thrust Ratio. E-Z Load Open Front Cap And Cartridge Retainer Spring.