The VS-210 Mini On-Camera Auto Flash from Bolt is a compact flash for use with both digital and film SLR cameras. It offers both manual and easy automatic exposure. An exposure chart on the back of the flash assists you when using manual exposure. The VS-210 features a guide number of 72' at ISO 100 and an adjustable tilt head with five set positions - 0, 45, 60, 75 & 90°. The flash covers a 35mm range (in 35mm/full frame format). The VS-210 is powered by 2 easily found AA batteries. The flash duration is between 1/2000 and 1/40,000 second.