Harris style bipod, also known as a "butterfly bipod".

• Black painted in colour.
• Features 2x positions where the legs lock - downward (engaged) and forward 90° (disengaged)
• External spring on both legs, for locking tension.
• Mounts to a sling stud, but with the included adapter, will fit to a Picatinny rail interface.
• Features double strips of rubber, on each side of the mating interface, to improve bipod traction to the rifle and avoid friction damage.
• Rubberized feet w/ concentric circle checkering
• When properly locked, the extensible legs will shoot out to the total length, at the press of the "scaffold" release button (see illustrated).
• Suitable for airsoft, paintball and PCP.

Feel free to have a look here;