Machined aircraft-grade aluminum with anodized finish. Available in black. LED available in white. Length: 1.47 in. (3.73 cm) Diameter: Head Diameter: 0.51 in. (1.30 cm) Body Diameter: 0.43 in. (1.09 cm) 0.36 oz (10 grams)* 5mm white LED, impervious to shock with a 100,000 hour lifetime. 10 Lumens Typical (White LED), Parabolic shaped LED area optimizes beam performance Rotating On/Off Head Switch Up to 8 hours declining useable output Four (4) IEC-LR41 coin cells. Non-rotating snap hook Most models meet applicable European Community Directives. Limited lifetime warranty