Smart Filament SensorBIGTREETECH SFS V2.0 can not only detect filament runout, but also filament breakage, filament clogging, filament tying and even extruder malfunction. Detecting above abnormal extrusion cases, BTT SFS V2.0 will send error alerts to screen and automatically stop printing to keep you away from filament and electricity waste. Sensitive Photoelectric Filament DetectorBTT filament detection module adopts photoelectric sensor whose theoretical detection length can reach up to 2.88mm, much shorter than 7mm of SFS V1.0. Such improvement enables SFS V2.0 longer service life and higher precision in filament abnormality detection. Note: 2.88 mm is the minimum detection length for the sensor to function properly. If false triggers error occurs, try to increase the detection length by 1mm until the problem is resolved.