designed smart module for detecting the status of the use of filament. To check the filament is whether run out or not, it automatically pauses the 3D Printer when the filament runs out, so you will have a to supplement the filament which makes you 't print a incomplete printing. Wear-resistant copper sets added in both the inlet and outlet to effectively extend the product life. is a very practical filament detection sensor module, Prefect accessories for 3D printer, making your printing work and relieved. Easy to install, and work steadily and durable in use. s: (for board) the green light keeps on when filament is in. If filament is exhausted, the green light goes off. At this moment, board pauses operation and it will continue to print after filament is in again. Working principle: The filament detection module uses the level transition detection . When with filament in, the detection level signal should be high, and when no filament, the filament port level signal goes low. When the system detects a determined transition from high to low level, it will regard it as the filament exhausted, then the board executes the pause operation, and after the replacement of the filament, it will continue to print. Specification: Colorblack material:PC+ABS Applicable filament diameter: 1.75mm/0.069inch Mounting hole size: 3.5mm/0.14inch Mounting hole distance: 20mm/0.79inch Wire length: 1 m/39.4inch Module size: 38 * 30 * 12.7 mm/1.50 * 1.18 * 0.5inch Motherboard wiring: M-sensor port Package Contents: 1 x Filament Detection Sensor 1 x Cable Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.