3 3/8" overall. Black HAIII military grade hard-anodized finish areo-grade aluminum alloy housing. Aluminum "unibody" construction is highly rugged and provides excellent cooling performance. White CREE XM-L2(T6) LED: up to 565 lumens, beam distance: up to 85m, runtime: up to 400 hours, candlepower: up to 1820cd. Red LED: runtime - up to 145 hours. Toughened ultra-clear mineral glass with anti-reflective coating. Ten rapidly switchable brightness modes to select from. Custom catoptrics-based system produces an extremely wide 100° beam angle. Light housing provides 90° vertical movement to eliminate illumination dead-zones. Innovative single button two-stage switch is remarkably user-friendly. Integrated red/green power indicator light displays remaining battery power. Power indicator secondary function displays battery voltage accurate to 0.1V. Integrated temperature sensor and intelligent temperature control ensure stable and safe use. High-efficiency regulation circuit provides unwavering output. Impact resistant: up to 1.5m. Waterproof: up to 2m (IPX-8). Includes a black, yellow and gray adjustable elastic nylon headband and space O-ring. Hang packaged. Purpose-designed for hiking, climbing, camping and general outdoor recreation.