The diameter of the DSLR camera rods is industrial 15mm standard
The 12'' 15mm rod is widely used on camera riser system and video making accessories, such as shoulder pad, lens support, matte box, follow focus, etc.
M12 inner thread on each end of a rod allows you to add a M12 threaded connector to lengthen the rail as you want
Comes with 2 pieces, the camera rails are well machining and finish
Black anodized aluminum alloy, sturdy and durable
Aluminum Alloy 12 Inch 15mm Rod with M12 Thread for 15mm Rod Rail Block Support System, Follow Focus, Matte Box - R053