1x Baseplate. Rails dia: 15mm. (Note: The 15mm Rods are not included.). Rails center-to-center distance: 60mm. You can connect a device with 1/4" screw on it, such as magic arm, etc. The tripod mount plate also built in 1/4" & 3/8" screw holes on the bottom to allowed be directly attached to a tripod or dolly or other devices, flexible of using.
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