Cantrell, the horizontal reticle needs to be at least 2,2" high. ----- google.com/search?q=how+tall+is+an+ar15+front+sight&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjnwvrNusHfAhWig-AKHRiEC_sQ_AUIDygC&biw=1280&bih=618#imgdii=sQB-xF8rgDIR3M:&imgrc=otapp_7yiHl8-M