Lightweight and compact: Sunpak's TR-2000 weighs slightly more than 24 ounces and measures 5 7/8 x 4 5/8 x 2 ¼ (HxWxD). As battery packs go, it's cute!
Event, wedding, and sports photographers who rely on shoe-mount strobe units need flashes that recharge instantly and reliably all day long. These guys can't be fumbling with AA cells, or waiting as pooped AAs take longer and longer to pop. They (and possibly you?) need high-power, rechargeable external battery packs to juice their shoe-mount flashes.
Not long ago, these power packs were three- and four-pound, lead-acid-powered bricks that no amount of finessing could hide under a sports coat. Then came NiCad and NiMH rechargeables, and size, weight, and pricing came down so that even average shutterbugs might consider buying an external flash battery pack. Such packs typically supply power to a flash's battery compartment via accessory cords.
Which brings us to Sunpak's TR-2000 power pack. A glance reveals some of its unusual features. Styling, for starters. We never thought we'd use "battery pack" and "stylish" in the same sentence, but the TR-2000, with curvy edges and matte-black surfaces (some rubberized) is more than just another black box.
Also unusual: The actual power cell (a.k.a. power cluster) snaps in and out of the TR-2000 proper. Heavy users can own several of the relatively affordable clusters, and snap them in and out as needed. Removing the cluster creates a somewhat smaller silhouette for added flexibility when packing a tight camera bag. Finally, this refinement lets Sunpak (uniquely) offer less expensive NiCad ($80, street price) or lighter, memory-free NiMH cells ($105, estimated street price).
The TR-2000 offers high- and low-voltage output (320 vcd/5.5 vdc). Having both options lets you use an inexpensive flash (such as the Sunpak 226D) as a back-up to fully dedicated, TTL unit, many of which accept the more convenient high-voltage option. Low-voltage operation requires a single-pin, RCA plug ($20-$30) the mates with the flash's battery compartment. High-voltage connections link via 10-foot, coiled, seven-pin DIN cords ($30-$40) that plug into special terminals in high-end flash units. Sunpak offers adapter cords for its own flashes ($33, list price). Quantum, Paramount and some others supply cords for most current flash units.