This quick attach system (support and tray) secures a camera monopod holder on various type stabilizer (Flycam) Flycam Nano stabilizer while maintaining the same 501PL plate, compatible with HDV Manfrotto 501 video head 501HDV Ball HDV Video Aluminium Black In my case, I have a tripod with a head and a stabilizer 501HDV "Glidecam HD2000", setting the MN-577 on the stabilizer, I do not need to disassemble the 501PL plate of my camera.
This set comes with 2 screws (1/4 "and 3/8"). There is a location on the side of the stand to place the unused screw. The bracket has 3 holes for immobilizing (2 holes 1/4 "hole 1 3/8"). The 501PL plate is compatible with joints and 701HDV 501HDV. A very good product Manfrotto.