Ideal for long-range centerfire shooting, Bushnell Rimfire 4-12x40 riflescope with .17WSM BDC reticle features Dusk & Dawn Brightness multi-coating, adjustable objective, multi-coated optics, one-piece tube, dry-nitrogen filled, 1/4 MOA windage and elevation adjustment, fast-focus eyepiece, and 100% waterproof, fogproof, and shockproof.