Feature A 30mm Extra Long One Piece Mount A Tactical Offset Style A Mil-spec Finish A Designed for Real Calibers Picture Specification A Mount Dia.:30mm A Overall Length:165mm (6.5 inch) A Base Length:90mm (3.5 inch) A Ring Gap:58mm (2.3 inch) A Ring Width:16mm (0.6 inch) A Weight:196g(6.9oz) A Height:38mm (1.5 inch, from bottom to the center of ring) A Finish:Black Matte A Mount:21mm picatinny A Offset style, 4 bolts per ring A Extra long style mount A High quality durable aluminum alloy A Designed for real fire caliber