Aluminum carabiner light with mini ruler, in US inches only. Ruler printed on side and measures 2 inches. 3 light settings, on reduced brightness, and blinking. Uses 2 button cell batteries, included and replaceable. COB 40-50 lumens.Item Size: 1.58 W x 3.15 H x 0.6 DImprint Area: 0.75 W x 0.5 H