1.Fit Picatinny Rail
2.Fit Barrel with adapter
3.Height (from top mount base to foot bottom): From 148mm to 163mm with various adjustment
4.Easy use and installation
5.Release and press down the button to fold the feet
6.Release the feet screws to extend the length
7.Rubbber Feet avoid slip
8.High durability aluminum alloy in black matt and beautiful complement
9.Can be used on real fire caliber.