Sekonic Transmitter Module RT-GX for L-858D Speedmaster light meter. Used to trigger Godox/Flashpoint-enabled lighting and receivers. Triggering and controlling the power level of Godox 2.4GHz wireless X system and Flashpoint 2.4GHz system built-in flash units Modeling lamp output power control with ON/OFF Wireless ID: (1 to 99 or OFF) Channel: 32 (CH1 to 32) Group: 16 (A to F, 0 to 9) + ALL HSS (High Speed Synchro) flash radio triggering is available For more information about Godox, see the website: http://www.godox.com/EN/index.html For more information about Flashpoint, see the website: https://www.adorama.com/g/Flashpoint_brand Note: This model may not be available due to the restriction of regulation in each country. Please be sure to check the radio frequency before purchase. For more detail about radio triggering, please see here. Catalog Numbers: SKU: 401-628 Measuring Range and Modes: Radio System: Godox wireless X system and Flashpoint system (2.4GHz) Physical: Operating Temperature: -10 deg. C to 50 deg. C Product Weight (lb): 0.02 Product Weight (kg): 0.01 Product Height (in): 1.1 Product Length (in): 1.3 Product Width (in): 0.47 Product Height (cm): 2.8 Product Length (cm): 3.3 Product Width (cm): 1.2 Startup Guide Safety Precaution CE Countries List Downloadable from website: Operating Manual Startup Guide Sekonic RT-GX Godox/Flashpoint Transmitter Module for the L-858D-U Light Meters Firmware