The Dead Level levels your reticle in relation to the Earth taking out any margin of error of the reticle not being perfectly level with the scope body. Simply attach your scope to the Dead Level, level the device with the precision thumbscrews to center up the bulls-eye level, then just level the reticle with a predetermined level line or plumb bob. Made from Aluminum with Mil. Spec. Anodized Hard Coat Type III, crimson and black. Instructions included. FOR USE WITH MIL STD 1913 and NATO STANAG 4694 COMPLIANT RINGS AND MOUNTSFeatures :Color - RedCompatible With - All Scope rings and mounts using Mil Std 1911Finish - Red/Black Type 3 Mil Spec AnodizingMaterial - Aluminum & SteelWeight - 1.53lb