Opteka 750 DG Super TTL Autofocus Dedicated Flash for Pentax K-30, 645D, Q, K-5, K-r, K-x, K-7 and Samsung GX-IS, GX-1L, GX-10 Digital SLR Cameras Works on all Pentax and Samsung Digital SLR Cameras Bounce capabilities in 5 steps up to 90 degrees; flash shooting distance range from 2 and up to 85 feet 35mm angle of coverage Guide number (ISO100) 26(m)/85(ft) at 35mm Advanced 2nd generation flash technology, only compatible with rechargeable AA batteries (Lithium, Ni-cd & Ni-MH)