The Shark Shim Large U Shim Clamshell Pack contains 60 durable, precision-made U-shims across four incremental thicknesses - 1/32" (1mm), 1/8" (3mm), 3/16" (5mm), and 1/4" (6mm) - designed for applications requiring greater load distribution and a larger bearing surface area. The open U-slot allows for lateral insertion around existing fasteners without the need for disassembly, while the larger footprint delivers enhanced stability under heavier loads. This versatile 60-piece assortment provides broad application coverage across a wide range of installation requirements.. The open U-slot allows for lateral insertion around existing fasteners without the need for disassembly, while the larger footprint delivers enhanced stability under heavier loads. This versatile 60-piece assortment provides broad application coverage across a wide range of installation requirements.