The Warne red dot riser mount was designed to offer easy height adjustments between absolute and lower 1/3 co-witness in one package to fit red dot optics. All riser mounts that we offer share a robust mounting base, while the top is engineered specially for different red dot styles. Our risers Include a .180" thick spacer. Fits the T1-T2, H1-H2, Crossfire, Romeo 5 Red Dot and Holosun 403, 503, 515, 530.