The B-Series of optics are the most feature packed optics on the market. While the B-10 retains the popular 1.8-10x magnification range todays professionals are asking for, the similarities stop there. These new optics now have locking elevation and windage knobs, zero stop, revolution counter, tool-less elevation zero and a single button illumination control which has been integrated into the parallax adjustment knob. All this and still the same durability, reliability and performance U.S. Optics is known for.