This set consists of 4 clamps, 4 threaded insert and a set of screws. The clamps are made of red oak. They are strong, but are less likely to shatter bits if they are hit. You should only need one set. The CAD file is provided so you can make your own if you damage one.
The clamps have an M6 threaded insert at one end. You can use the provided M6 carriage bolts to adjust the height of the clamp. This allows you to adjust the clamp so that is less likely to damage softer materials.
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