TTL Compatibility: Nikon i-TTL Frequency: 433MHz Channels: 52 Channels over 26 Frequencies Antenna: 6.9 cm rubberized with 180 degree swing Transmit output power: Less than 0.001 watt (1/1000 of a watt or 1 milliwatt) Maximum Range (In optimum conditions): 240 Meters) for i-TTL triggering 365 Meters for standard triggering Mounting: Hot Shoe, 1/4-20, lanyard, velcro Maximum Shooting Rate Frames per second (fps) 8 fps for E-TTL II and normal triggering Power / Channel Switch OFF - C.2 - C.1 Zone Select Switch A-B-C (matches Canon slave groups) Status Indicator LED: Green, Amber, Red status indications Camera / P1 Port 1/8" (3.5 mm) stereo miniphone for 2-stage remote camera triggering. Port Voltage Handling: up to 50 Volts, 100 milliamp continuous Tip = Trigger Ring = Pre-Trigger Sleeve = Ground Flash / P2 Port 1/8" (3.5 mm) mono miniphone. Port Voltage Handling: up to 200 Volts, 4 amps peak, 250 milliamp continuous, non-polarized Minimum Receive Contact Time Camera / P1 Port = 80 milliseconds Flash / P2 Port = 500us Voltage Present 3.3 VDC (all pins) - safe for all cameras Hot Shoe voltage protection: Hot Shoe: up to 50V USB: USB Compliant 2.0, Mini-B Connector, 5VDC regulated, 100mA, Pin 1 Positive, Pin 4 Ground Operating Temperature Above -15° C and below 50° C Storage Temperature (without battery) Above -30 C and below 85 C Construction High impact plastic, captive battery door Hot Shoe made of glass reinforced resin Power: Two (2) AA (IEC:LR6) Alkaline recommended, other chemistries (NiMH, NiCAD, Lithium) allowed, USB Battery Life 60 + Hours Dimensions 9.2 cm long x 7.3 cm wide x 3.6 cm tall, antenna lowered Weight 153 gr. or 108 gr. without batteries