The 02913017 model by Daniel Defense adds flexibility to your AR-type rifles with Mil-STD 1913 rails. This 1 O\'clock Offset rail is specially designed to facilitate quick, non-magnified transitions when using magnified primary optics. Mount your miniature red dot optics at the 1 o\'clock position for right-hand use or the 11 o\'clock position for left-hand use. Most importantly, this offset design maintains the same cheek weld position during transitions, ensuring better control and accuracy.