.177 cal 5.56 grains Domed Lead-free 100ct Gamo is always inventing new ammunition to help your guns shoot faster, to deliver a flatter pellet trajectory, to minimize lead contact for you and your barrel, and to increase accuracy. The Gamo Lethal pellet has a polymer skirt that's been lengthened over the conventional skirt size and has a brass insert for the head, which is labeled as a dome but actually seems to fall between a semi-wadcutter and a typical dome. Gamo states that their Lethal pellets deliver 38% greater accuracy over lead pellets. The brass head delivers quite an impact and can penetrate a metal plate that's 0.06 inches thick.