Type of Speedlight: TTL auto-flash speedlight with built-in AF Illuminator. Guide Number: GN: 125 (ISO 100 at 35mm in feet). Bounce Capability: Flash head tilts down -7 degrees or up 90 degrees. Flash head rotates horizontally 180 degrees to the left or 90 degrees to the right. Automatic Balanced Fill-Flash with TTL Multi-Sensor: 3D Multi-Sensor Balanced Fill-Flash, Multi-Sensor Balanced Fill-Flash, Matrix Balanced Fill-Flash, Center Weighted Fill-Flash/Spot Fill-Flash, Manual Power Mode for F5, F100, N90s, N80 or N65 Flash Output Compensation: +3 EV to -3 EV in 1/3 EV steps Wireless Control: Can be used off camera with TTL control to approx. 23 feet. Up to approx. 131 feet in manual mode. Slow and Rear-Curtain Sync: Controlled from camera position. Camera sets exposure from 30 seconds to highest sync speed to balance. Ready Light: Lights up when SB-80DX is charged and ready to fire, blinks when flash fires at its maximum output, indicating light may have been insufficient (in TTL auto-flash mode). Wide Flash Adapter: Allows the SB-80DX to be used with lenses as wide as 14mm LCD Indications: 3D Multi-Sensor Balanced Fill-Flash, Matrix Balanced Fill-Flash, Flash Output Compensation, Flash Zoom Head Position, Audible Alert Warning, No AF-Illuminator, AM, Slave Function. Modeling Flash: Available. Zoom Range: 24-105mm. Slave Sensor: Senses light received from the master flash unit in wireless multiple flash operation. Red Eye Reduction: Available. Power Source: 4 AA Lithium batteries (See manual).