MFR-150D Macro Focusing Rail with screw-knob clampT6061 aero space grade aluminum alloy main body, stainless steel lead screw, elaborately CNC machined ensures its stability in use without any wobbling. Exquisitely CNC machined ensures its smooth and quiet in use; Rail length 150mm, weighing only 338g, easily carried; Load capacity of 7kg; Uses high precision lead screw, the clamp moves 1. 25mm per revolution of the lead screw; Index marks on each end of the lead screw provide easy reading and