Our B2 Set contains a generator, two heads, and two batteries with a charger. Please add more batteries and a TTL transmitter if needed. Also, a Bracket is available to mount the b2 head on a camera. The B2 250 Air TTL To-Go Kit from Profoto is an ideal way to get into the game-changing battery-powered flash system that includes the B2 250 AirTTL Power Pack, Flash Head, and tailor-made OCF (Off-Camera Flash) accessories. The kit includes the pack, a battery, charger, 1 B2 flash head, padded Location Bag, and a Carrying Bag with shoulder strap. Complete the kit and get full wireless TTL operation with the purchase of a dedicated AirRemote TTL transceiver for your Canon or Nikon Camera. Intended for the road, the B2 250 AirTTL Power Pack measures 6.3 x 3.1 x 6.7" and weighs in at just 2.2 lb with its Li-Ion battery. The B2's twin outlets each have a dedicated thumbwheel that allows the pack's 250Ws of power to be distributed asymmetrically over a 9-stop range in full or 1/10 steps. The digital LED screen that displays the power settings is also the key to the pack's many capabilities. The B2 boasts recycling times from 0.03 - 1.35 sec., and an action-stopping flash duration of 1/1,000 sec. There is also a Freeze Mode that selects a flash duration of 1/15,000 sec. at lower power settings - fast enough to "freeze" water droplets, spray, and splashes. Bursts of up to 20 frames per second are possible while High-Speed Sync allows shutter sync speeds from 1/4,000 - 1/8,000 sec., giving you wide ambient light control options. The pack's Li-Ion battery can be charged in or out of the pack and will give you up to 215 full-power flashes on a 45-60 minute charge from a multi-voltage 2.8A battery charger or a trickle charge from an optional car charger. At 1.5 lb, the sturdily built B2 Off-Camera Flash Head measures 4" long, has a 3.9" diameter and fits in the palm of your hand. A barely-visible umbrella channel runs through the top of the head, while its tethered 6.5' head cable can be lengthened with a 9.8' extension for large groups or for hanging in hard to reach places. An included stand or pole-mount with a ratcheting handle can be removed for mounting to a flash bracket. The B2's flash tube and 50W halogen-equivalent LED modeling lamp are protected by a frosted glass plate, while its 3.9" diameter housing accepts a line of optional accessories that includes OCF-tailored softboxes, barndoors, a snoot, and a grid set. They can also be used on the B1 battery-powered monolight.