The Macro Focusing Rail with Screw-Knob Clamp from Sunwayfoto gives you the ability to precisely adjust your camera fore-or-aft when shooting macro photography. The clamp at the top is Arca-type compatible and locks down with a screw-knob. The focusing rail itself has a double-dovetail mount and will fit most Arca-type clamps on the market.

The Macro Focusing rail has both a ratchet handle, for fast and quick adjustments, and a thumb-screw knob along with engraved index marks on the side of the rail for fine adjustments. The CNC machined T6061 aluminum rail holds a maximum weight capacity of 15.4 lb, but may hold less weight once the angle of the rail is changed.

The Type III black anodized aluminum is scuff and scratch resistant and the finish is also resistant against corrosion. In addition, two focusing rails can be stacked for dual axis adjustments (fore-or-aft and lateral). Located on the bottom of the plate are two safety stop screws to prevent any accidental pulling or falling out of the rail when a clamp is partially open.

Adjustment Range     Lead screw: 4.2" (106 mm)
Total Adjustment Range: 8.7" (220 mm)
Stage Travel per Revolution: 0.05" (0.125 mm)
Thread Pitch     0.5 mm (12.5 mm)
Weight Capacity     15.4 lb (7 kg) weight capacity varies with angle of load
Dimensions     8.5 x 2.1 x 1.3" (21.6 x 5.3 x 3.3 cm)
Weight     9.8 oz (279 g)