ACR Life preserver signaling emergency strobe - Product No. 3959 Intense strobe light visible up to 2 miles (3.2 km) Waterproof and corrosion resistant case Slim, lightweight design Comes with an adjustable Velcro strap; can be mounted on bicycle frame or pole, etc. Operates on 2 "AA" alkaline or 2 "AA" 1.5V lithium batteries (5-year replacement life when using lithium batteries; 1-year replacement life when using alkaline batteries) Operating life - More than 8 hours continuous @ -1°C (30°F) Size: 6.0 x 1.6 in (15.3 x 4.0 cm) Weight: 2.6 oz (74 g) Material: Rugged, impact and temperature resistant ABS Color: International orange Operation: Twist "ON-OFF" control can be operated by gloved hands and in adverse conditions Waterproof: Up to 10 ft (3.1 m) Accessories: 1083-Dated lithium/sulfide batteries Beam Angle: Omni-directional 360° Visibility: High intensity strobe light is visible up to 2 miles (3.2 km) Flash Rate: 60 ± 10 flashes per minute nominal Lamp: Xenon flash tube Battery Type: 2 "AA" alkaline or 1.5V lithium (not included) Certification: USCG 161.012/41/0 approved with 2 "AA" lithium or alkaline batteries; CE Limited Warranty: 1 year Carton Dimensions: 3958 - 7.0 x 12.0 x 5.0 in (18.0 x 30.0 x 13.0 cm) 3959 - 13.5 x 13.5 x 9.0 in (34.0 x 34.0 x 23.0 cm) Units Per Carton: 3958 - 24 / 3959 - 12 Carton Weight: 3958 - 4.8 lbs (2.2 kg) / 3959 - 4.5 lbs (2.0 kg) Operational Life: More than 8 hours continuous @ -1°C (30°F)