### Pure Mechanical Filament Protection This filament cutter is a purely mechanical accessory that detects filament tangles and knots through tension. When the extruder pulls on a stuck filament, the internal mechanism converts the pulling force into shearing force and cuts the filament instantly. No power, no heat, no signal required. ### Protect Your Prints from Air Printing Filament tangles are hard to spot visually and may only cause problems hours into a print when the knot tightens. This cutter automatically cuts the filament when a tangle occurs, triggering the printer's filament-out sensor and pausing the job before air printing can ruin your print. ### Works with Automatic Feeder Systems After the filament is cut, the AFF (Automatic Filament Feeder) retracts the failed filament and automatically splices in the backup filament, enabling true continuous unattended printing. No more wasted prints due to tangled spools. ### Easy Installation and Reset Mount the FC cutter along your filament path between the spool and the printer. The arrow marks spool direction. Insert PTFE tubes into the inlet and outlet connectors. The green reset window confirms normal operation. Pull the slider manually if reset is needed. ### Complete Kit with Spare Blades The package includes 1× Filament Cutter, 3× spare blades, spacer ring, ceramic eyelet, stainless steel screw, and 4× mounting screws. Everything you need for installation and long term maintenance.