When used in combination with Nikon's latest digital SLRs, the D70 or D2H, the SB-600 supports Advanced Wireless Lighting as a remote Speedlight that can be positioned as one of multiple remote flashes to significantly extend creative possibilities. To assist in such situations, the Speedlight SB-600 also has a readylight located beside the LCD on the rear panel that can be easily seen from a distance. The SB-600 can also emit an audible alert for further assistance. Easy-to-view LCD with 6 simple-to-understand backlit buttons Guide Number of 30/98 [ISO100,m/ft], 42/138 [ISO200,m/ft] (at 35mm zoom) Auto zoom of 24 to 85mm, extendable to 14mm with built-in wide-flash adapter Advanced Wireless Lighting available with D2H or D70 when used as a remote Auto FP High-Speed Sync (with D2H only); use with fast shutter speeds achieves effective blurring of out-of-focus background elements Flash Color Information - optimized white balance makes use of data from the Speedlight FV lock holds flash value, enabling recomposition prior to shooting Design consistent with those of next-generation D-SLRs, with a triangular design element on the top that complements the D-SLR motif Requires 4 AA Batteries (Alkaline or Rechargeable NiCad or NIMH) for use