Solid mount - Midwest Industries T1/T2 Red Dot Optic Mount

This is a nice semi-permanent mount. Attach your optic then slide it onto your upper receiver rail from the back, insert the cross bolts, and tighten down. Virtually impossible to come off unintentionally.

Another reviewer rated it poorly because it didn't put his holosun sight at lower 1/3. Holosuns and aimpoints don't have the same height. A little investigative internet searching on his part would've made that apparent. This is not advertised as a holosun mount, but most aftermarket sights for aimpoint micros will fit certain holosun RDS's. Absolute co-witness height aimpoint micro mounts will put holosun 403 and 503 series red dots at about 1/3rd co-witness height.