Designed for Hook-On Bed Rails Bed Claw® Anti-Wobble Bed Rail Shims are designed for use with hook-on bed rails and bed frames. Snug Up the Bed Frame They are ideal for use with wooden beds, because they allow you to "snug up" the frame and prevent wobbling, shaking, squeaks, and damage to hook connectors from excess movement. Simple Installation You place these between your headboard / footboard and the bed rails, placing the hook connector through the slot in the shim, then simply connect your bed back together as you normally would. Minimum Quantity Minimum quantity is 4. What is a shim? By definition, a shim is a thin strip of material used to align parts, make them fit, or reduce wear. Depending on the gap multiple shims can be used together to provide a snug fit which can help reduce any unwanted movement or sounds being made by your bed frame. The sounds are simply two pieces of the frame moving back and forth on each other. Along with stopping the movement and sounds, properly installed shims will help reduce wear and tear since the frame will no longer be scraping against itself. Registered Trademark Bed Claw® and the stylized bedCLAW® logo are registered trademarks of Homeplace Group, Inc.