PGYTECH Arca-Type Quick Release Plate Extra secure and efficient Arca-Swiss compatible It's compatible with the Arca-Swiss and MantisPod Pro and other products designed with SnapLock system. Patented tight-fitting screw The tight-fitting screw avoids it getting undone like traditional quick release plates often do. PGYTECH Quick Release System We have found that photographers often need to detach and mount the quick-release plate all the time. However, most Arca-Swiss compatible designs use the very inconvenient rotation knob. That's why we designed the patented SnapLock System, which includes a SnapLock plate and SnapLock mounting base. The SnapLock mounting base and plate are both Arca-Swiss compatible, and clamp / lock in only one easy step. The SnapLock plate uses a patented tight-fitting screw containing a thrust needle roller bearing, which effectively reduces the friction of the rotating surface. It ensures the screws don't rotate when attaching your camera, which ensures the plate doesn't get undone like traditional quick release plates often do. Below is the standard size of the SnapLock Plate: