For what it is worth I have the Kirk BL-D3 L-Bracket on my D3S which I removed and put on the D4. It fits the contour of the body frame properly. The access to the battery chamber works well. The only thing is the access to the peripheral conncetion is a bit hard to open but it does give you access. But the headphone/ext microphone connection will not open, you would have to open the flap before mounting the bracket. All to say if you want to save some dollars you can use the above mentioned bracket if you have it already.