The KonusPro 550 takes the guess work out of hold over angles for even the most difficult of shots. The exclusive ballistic reticle, coinciding with the most popular center fire loads today, provides you with a system of reference lines for exact aiming points out to 550 yards. Lateral hash marks allow for precise leads of moving targets as well as compensating for strong crosswinds. The glass engraved ballistic reticle is unbreakable, and has a dual illuminated red and blue center dot for shooting into dark targets, as well as during the critical dawn and dusk time of day. The multi-coated optics are clear and bright.Features : Waterproof, Fogproof, shockproof Dry nitrogen filled Fast focus ocular Heavy caliber recoil proof reticle Fully multi coated optics