I got this Sunpak PF30XN for my son, his Nikon D40 built in flash was giving him problems. Recived it fast withno problems. I tryed it out on my Nikon D3000, every shot taken came out just fine. I was using my 200m zoomdoing shots up close and 20' acrose the room....this flash has a high guide number and you can tell. This isa nice flash much better than the one Nikon has built in.