JTZDP30 Universal Quick Release QR Baseplate 19mm Rod Rig for Follow Focus Matte Box Canon 5D III Sony A7 II GH4/5/5s FS5/7 Blackmagic Ursa Mini BMPCC 4K DSLR Camcorder Cameras, Arri Rosette Mount

This is a 19mm Bridgeplate. It's labeled as a baseplate, however, it is not a baseplate, because a baseplate is what directly contacts the bottom of the camera, and this is not something you directly screw on to your camera. It is a bridgeplate.To use this properly and have the correct 19mm iris rods distance from center of rod to optical center of camera, you need the correct 15mm baseplate for your specific camera. There is no universal 15mm baseplate, each one is specific to your particular cinema camera. Then you attach this 19mm rod bridgeplate to that baseplate. So, you will have 2 sets of rods from 2 plates under your camera.This is something that's not easily found online. That said, this is the best value you can get for you money for a 19mm rods system. Other manufacturers charge a price higher than this set for just the 19mm bridgeplate. JTZ gives you not only the bridgeplate, but also 14" long rods, and a safety dovetail. Individually from almost all other manufacturers, that's almost double the price of JTZ's asking price for this set, so this is fantastic value. However, please know you need the correct baseplate for your camera first, attach that directly to the bottom of your camera or your camera in its cage system, and then you attach this bridgeplate to the bottom of that baseplate to get the correct height. If you don't do that, matte box, follow focus, lens supports will all be too short.