Pentax AF-200FG Electronic Flash with Case Compact design Guide number of 20 at ISO 100/m Simple mode dial operation Clip-on P-TTL auto flash system; includes case Guide Number 20 at ISO 100/m, 28 at ISO 200/m Approximately 300 (alkaline), 400 (NiMH), or 450 (lithium) discharges per set of 4 AA-size batteries Discharge angles of 70 horizontally (78 with wide-angle panel), 53 vertically (60 with wide-angle panel) Uniformly covers the wide discharge angle of a 28mm lens (in the 35mm format) Clip-on P-TTL auto flash system; includes case Guide Number 20 at ISO 100/m, 28 at ISO 200/m Approximately 300 (alkaline), 400 (NiMH), or 450 (lithium) discharges per set of 4 AA-size batteries Discharge angles of 70 horizontally (78 with wide-angle panel), 53 vertically (60 with wide-angle panel) Uniformly covers the wide discharge angle of a 28mm lens (in the 35mm format)