Godox TT685N i-TTL 2.4G Wireless Radio System Master Slave Speedlight Flashlight Speedlite for Nikon D7100 D7000 D5200 D5100 D5000 D3200 Two transmission ways, optic transmission and 2.4G wireless transmission, better to meet your needs. Powerful flash with guide number 60m at ISO 100. Supports multiple flash modes M/RPT/Multi. Support high speed sync, 1st curtain snyc and 2nd curtain sync, the maximum shutter sync is up to 1/8000s. The 2.4G wireless triggering distance can reach up to 100m, better to meet your needs.