Featherboard

A featherboard is a board with a series of thin, flexible fingers cut into one end, clamped or bolted to a table saw or router table so the fingers press a workpiece firmly against the fence or table as it feeds through. The fingers flex forward under pressure but resist moving backward, so they maintain consistent contact through the cut and, critically, block the workpiece from being thrown back toward the operator if something goes wrong.

Beyond the safety benefit, a featherboard also improves cut consistency -- constant spring pressure against the fence holds a board's position far more reliably through a long rip cut than hand pressure alone, which naturally varies as a board is fed forward.