Quick Flip Open See Thru Lens Cover Caps for 30mm Tube 1X30 1X28 Red Dot Sight A pair of qucik flip open lens caps that will mount onto typical 30mm tubes of 1X30, 1X28 red dot sights Made of soft rubber with spring loaded see thru flip open plastic cover Lens length from front to back: 20mm Red dot sight needs to have outside diameter of 30mm and straight ends on both ends of the sight for the caps to fit