Water resistant to 100 feet (30m),On/Off switch conveniently located on side of battery compartment for easy access when wearing headlamp. Adjustable head strap made of stretch elastic, comfortabley fits all head sizes. Adjustable inclination with 5 vertical positions that ratchet Up/Down to direct beam at desired angle.Includes 3 AAA 1.5 volt alkaline batteries.Ultra Lightweight - 5 ounces with batteries, 3.5 ounces without batteries.