Popular red shotgun sight with a 6mm self adhesive base and a 3mm diameter red fibre optic bead. The bright Ruby shotgun sight can help you to shoot with both eyes open (eye dominance correction) due to being highly direction sensitive, this means it can only be seen when looking right central down the rib. Incorrect eye dominance is very common and is a major cause of missing the target, as is lifting your head from the stock. This sight helps to reduce both shooting habits. It is also helpful for shooting in poor light. Easy to fit - includes alcohol wipe and instructions.