Just passing along something which may be of interest. I had been looking for a quick release plate that would include a tripod screw and secondary screw or stud at 1.25 inches apart, since that's the distance between holes on the base of my recently acquired used field camera. I had thought I could use my Manfrotto hex plates and drill an extra hole for a threaded pin at the edge, but the distance is just a wee bit too great.

I came across this item on the auction site, sold by various vendors for around $12: http://www.ebay.com/itm/332259716373. Advertised as a video or DSLR QR plate, I just got mine and like it. The design is good, materials and finish adequate. Although I haven't seen extra inserted plates available, for this price, I could buy another unit and simply use the second plate on my 645 camera.

The Manfrotto hex plate (or other QR plate) screws into the bottom of this unit, then I attach the QR plate to the camera. The maximum potential distance from primary attachment crew to the stud is nearly 2.25 inches. It is very snug and non-slip, with no wiggle. My camera weighs less than 5 lbs with a lens; this might not suit a heavy camera -- it seems to be cast metal, certainly not forged steel -- but it seems quite solid and stable indeed.

As shown, it comes with 3/8- and 1/4-inch screws; either can be removed easily and threaded holes are provided on the side for storage. Pretty neat.