The Phottix Strato II Multi 5-in-1 Receiver for Nikon offers four groups (A, B, C and D) and extended range to the already impressive functions of the original Phottix Strato. Four groups combined with four wireless channels allow photographers an incredible amount of control on location or in the studio. Sixteen or more hot shoe flashes or studio strobes - ready to be used at the push of a button. The Strato II Multi is compatible with original Phottix Strato receivers. That's right, it's backwards compatible The Strato II Multi can be used as a flash trigger, or wired/wireless shutter release. Set up four or more cameras and take photos from multiple vantage points from one location. Great for sporting or other special events.