Nikon Speedlite SB-20

• Light output control: Silicon thyristor-controlled rectifier and series circuitryAutomatic TTL flash output control with Nikon F501 (AF assisted), F301, FA, FE2, or FG; automatic exposure control with any Nikon SLR (with Flash Unit Coupler AS-4. AS-7 or AS-17 required with Nikon F3); manual control: choose from full, 1/2 1/4 1/8 and 1/16 output Guide number (ASA/ISO 100 In feet) 100 with zoom head set at N
• Angle of coverage: 45° horizontal and 60° vertical; with zoom head set at N
• ASA/ISO film speed range: ASA/ISO 25-1600
• Recycling time: Approx. 7 sec
• Number of flashes: Approx. 150* AF assist LED Automatically fires LED beam at the subject when below predetermined level of brightness when F501, F801 etc. is set at Single AF Servo mode. * With fresh alkaline-manganese batteries at full output
• Power source: Four 1.5V AA-type penlight batteries
• Dimensions (excluding mounting foot): Approx. 2.8″(W) X 4.3″(H) X 2.7″(D) (71mm X 110mm X 70mm)
• Weight (excluding batteries): Approx. 9.2 oz. (260g)
• Other features: Ready-light, open-flash button, sync/multiple flash terminal Accessories provided Soft Case SS-20

see this page for compatability