The Davis & Sanford RD2 Camera Platform with 3/8" Screw provides a 3/8" screw connection, and fits on Davis & Sanford's tripods that feature a 1-7/8" diameter open center column (centerpost), e.g. models A, Mark II, ETVG, PSG, Maxi-60HD and Maxi-75PF. Allows for quick and easy head attachment and removal.