The i2R Hold Down Clamps are a handy accessory to keep your workpiece secure and stable during machining. Sold in a pack of two, they can hold any material up to 3" thick. The 5/16" T-bolt slides smoothly into the table T-slots of the i2R CNC Routers. The clamping arm is anodised aluminium which won’t mark your materials, and features a large, knurled handle for easy tightening.-bg