Well, to begin with, composite (plastic) fasteners can be routed and sawn, so they're ideal for holding work to a CNC spoilboard. They are also great for running manual jigs through a table saw, or across a router table. The opportunity to replace clamps, vacuum pods or other devices on a CNC means that spindles and aggregate heads will have more room to move around with hitting something.
Losing C-clamps or similar mechanical devices on manual jigs makes them a lot less cumbersome, and often a lot safer. Ever clip a clamp with a bit or blade? Plus, the work is more stable when permanently nailed than temporarily clamped. Composite fasteners don't rust, so they're ideal for boats, outdoor trim, and even tagging the ends of boards at mills or lumberyards.
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