otw flip up sight 45 degree offset rapid transition front and backup rear sight iron sight otw <b>flip up sight 45 degree front sight and rear sight is rapid transition.</b><p> <b>two mode to aim as front sight has two kinds of reticle.</b><p> <b>iron sight is aluminum-alloy construction. </b><p> <b>specification:</b><p> black anodized finish <p> 20mm picatinny weaver rail <p> <b>parameters:</b><p> meterial:aluminum-alloy <p> weight:4.1oz/116.2g <b>box include:</b><p> 1 x front sight <p> 1 x rear sight <p> 1 x allen wrench <p>