i read that windage and elevation was switched during manufacture

http://www.gibbsrifle.com/images/p004_0_02_01.jpg
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M73B1 Riflescope & Mounts -



This is an exact copy of the U.S. M73B1 sniper scope, features a 3/4" blued tube, thin crosshair reticle and windage & elevation adjustments identical to the original. Prod #M73B1. Available Fall 2009.