Dear Fringer Contax 645-GFX adapter users,
According to a couple of users' feedback, with very low possibilities, the foot (tripod mount) of the adapter may not be fully compatible with some of the Arca style quick release clamps in the market. It may not be tight and secure enough even the screw is tightened. Because we have to take care of handheld usage as well, there are no safety stop screws under the foot. Thus, if you mount the foot directly to a Arca style quick release clamp, make sure it's installed tightly and securely. Or you may consider installing an additional quick release plate with safety stop screws to the food through a 1/4" screw. Then install the quick release plate to the clamp.