Huben K1 in 5.5mm semi-automatic .The rifle is in great condition and is absolutely tight. I shot the rifle a few times, very little signs of use on the adjustment screw for regulator and on the adjustment screw for the spring. But you can't see them from the outside, only when the rifle is disassembled. Among them is: -Muffler adapter -Slugs new pack -Shoulder strap -Bipod adjustable in 3 positions -Rifle scope Westhunter 4-14x44 SFP -Replacement seals - Original packaging.