Height without Insert: Absolute Co Witness Height with Insert: Lower 1 3rd Co Witness T1 T2 Type Interface Fits T1 T2, H1 H2, Crossfire, Romeo 5 Red Dot, Holosun 403, 503, 515, 530 Includes .180 in Thick Spacer Designed and Made in USA The Warne Aimpoint T1 modular mount was designed to offer easy height adjustments between absolute and lower 1/3 co-witness in one package to fit all T1/T2 interface red dot optics. All riser mounts that we offer share a robust mounting base, while the top is engineered speci?cally for different red dot styles.