BatterySpace.Com Bike Light: 20W Dual Halogen Light plus 14.8V 4Ah Li-Ion Flat Battery and Smart Charger, part number BM-HL001C02. It features two independent light heads - the direction of each light is individually adjustable. The dual light heads mount onto the handlebar using a relatively permanent mounting bracket. That is, the low profile mounting bracket is bolted to the bar. It is made of durable and lightweight construction of CNC machined aluminum.

Super bright dual MR11Halogen lamps: 5w ( flood ) and 15w ( Spot ) lamps for a total of 20watts of halogen power when running both flood and the spot options at the same time. It comes with an easy to use clamping fixture that allows mounting to any bar of your bike in the range of 0.375in to 1.125in with no shims needed. It also has an easy to use waterproof thumb touch switch for changing the lighting options: Spot light On, Flood light On, and All-On. The switch lead is approximately four inches long so you can have the lights in the center of your bars, and the switch will mount next to your grip for safety and convenience. It weighs about 4.5 ounces.

The manufacturer’s stated burn time using the 14.8V 4Ah Li-Ion battery pack is at 5W is 12 hours ; at 15W: will be 4 hours; and when using the total 20W you will get 3 hours. Of course real world time is less.

One High capacity 14.8v 4000mAh Li-Ion battery pack that comes in its own really nice nylon bag. The bag has two zippered pockets. One compartment is for the battery and the other smaller front compartment for miscellaneous small items. The bag’s dimensions are 5.5" x 3" x 3” making for easily carrying the battery on your belt or on the top tube of your bike The high capacity Li-Ion battery is rated at 14.8V, 4000mAh , and is made of 8 pieces matched 18650 Li-Ion cylinder cells. It is fairly lightweight and compact in size at about 14 and the dimensions are 3 x 2.5 x 1.5 inches.

It comes with a six-foot long cable with female connector to fit in both the smart charger and halogen lighting system.

It comes with a multi-level Smart Li-Ion battery charger for recharging the battery pack. The smart charger has 120-240V AC input for worldwide voltage support. There are four levels of voltage selectable on the charger, for example, 3.6V, 7.2V, 10.8V, and 14.4V. For charging 14.8V battery pack, you must choose voltage switch to 16.8V level. Charging time for the 14.8V, 4000mAh Li-Ion battery is about 8 hours.

To sum up: This is a very bright, easy to use and mount, with long burn times, excellent modular light system, The price tag is very reasonable when compared to similar dual beam systems. I travel to work 3 to 4 times per week and have unpredictable hours. My biggest fear on the road is to be hit by a car in the middle of the night. Cars, and pedestrians have not ignored me yet when I am flashing my 20W at them. If you are uncertain whether you want a dual or single beam system, go with the dual lights.