aviation aluminum, machining, hollow weight reduction design, polishing and surface anodizing treatment, beautiful appearance and fine workmanship Quick release plate is AS 39mm standard, for / ARCA-SWISS / / WIMBERLEY / MARKINS / SUNWAYFOTO / KANGRINPOCHE / / ISHOOT ball for head of Arca 39mm fit Designed with two bottom quick release plates, both are ARCA-SWISS standard Metal tripod mount stand replacement base foot for RF 600mm F/11 IS for & RF 800mm F/11 IS for telephoto lenses, vertical end of the bottom plate is locked with spring screws, and 1/4 screw holes and 3/8 screw holes are reserved; the other end of the floating plate is reserved for 1/4 screw holes