Overview: Model: WRSS1 Radio frequency control, 16 channels Dual color LED indication Support " Bulb Exposure" control & continuous shooting control (corresponding setting on DSLR required) Available in a long distance (lt;100m) Powered by 1x 23A & 1x CR2 battery (both included) Compatible with SONY a 100/a 200/a 300/a 350/a 700/a 900, MINOLTA a 7D/a 5DSpecifications: Weight: 4.58