His is a Pro'sKit SN-390 Adjustable Soldering Clamp Holder, a soldering jig featuring 360-degree rotation and four clamping thicknesses.Max Clamping Width: Accommodates circuit boards up to 200mm.Rotational Capability: Allows for 360-degree rotation to easily flip the PCB.Construction: Features a metal base with ABS arms and non-slip rubber pads for stability.