This is not a rifle bench rest as it pivots at center bottom - Hyskore Black Gun Shooting Rest

The pivot axis of this device is at the center bottom. Think fixed automatic weapon as in a turret or post mounted MG on a vehicle. I jumped at the sale price thinking it was their very similarly described bench “machine rest” which was over twice what this thing cost. Luckily I stared at the box before opening; they sent a printable postpaid return lable. To be direct, this puppy would require that you crouch behind and raise and lower your torso for elevation.