SMALLRIG Clamp Baseplate for ARRI Standard - 1509 SmallRig Dovetail Clamp for Arri Standard Plate 1509 can attach to a tripod plate for Arri Standard. It is specifically attached to base plates or rod clamps or any other rigs by 3/8"-16 & 1/4"-20 screws. There is a safety pin on each end. It is light, handy and convenient, and perfectly fits SmallRig Dovetail Clamp 1683.