I pretty much figure I know the answer which is no, ptz wall mounts are not universal at the connection spout to any camera you want to attach to it. I'm looking to put a megapixel (preferably dahua) ptz in place of my analog ptz and ideally I want to keep the ptz mount to make the install a breeze. Besides understanding that different cameras have different top mounts, I guess what I'm getting at is the diameter of the tops of ptz's that look to be similar to the ptz I have in place now. I'm wondering if the top of a given ptz that looks right, the top being 'male' will fit into the 'female' spout of the mount. Are diameters universal at all, or is the top of every ptz proprietary to its own mount? My avatar pic is the ptz I want to swap out. It's tough because obviously you can't buy a camera and just see how it goes, at least not without a ton of trouble. Any thoughts?