Geonox Airsoft goes over the airsoft version of the pistol associated with the U.S. Navy SEALs, the SIG P226... "In this video we look at the P226 MK25. It is a GBB (Gas Blowback). The advantage of GBBs is the kick and the fact that the slide snaps backwards with every shot. A big highlight with this model in particular is that the hopup can be adjusted from the outside. You don't have to remove the slide to adjust the hopup like with conventional GBBs."