1, 30mm scope mount 2, Six Bolts 3, Heavy Duty 4, Low Profile Model: ... : 27mm (1.1 inch from the base bottom to the ring center)Weight (net): 150g (5.2 ounce)Fit on 21mm ... railHigh quality aluminum alloy in durable black matte finishSix bolts ring style in heavy dutyShock proof can be used on real ... control Vector Optics 30mm Tactical Low Profile Riflescope Weaver Scope Mount Ring Heavy Duty