Phottix Strato TTL Flash Trigger for Nikon (Rx Only) • 4 groups: A, B, C, D • 4 Channels • 150+ m range • 1/250 sec. sync speed* • Flash wake-up functions* • Hot shoe / PC Flash triggering • Studio strobe triggering • Wired & wireless shutter release functions • Pass-through hot shoe on transmitter allows on camera flash to use TTL functions • 2.4 GHz. frequency • Uses AAA batteries • Compatible with Phottix Strato™ 4-in-1 Wireless Triggers Extra receivers for the Phottix Strato II system. The Phottix Strato II Multi 5-in-1 Wireless Trigger System gives photographers incredible control over their flashes & Monolights. Four channels & four groups provide unparalleled control in the studio or on location.