The FSR 404 model is a single zone ForceSensingResistor based on the FSR 402 ®， But there is a hole in the middle of the design that can be used for applications that can be installed on protrusions, bolts, or other protruding parts. Although many sensors in the 400 series have been optimized for human touch control in electronic devices, this sensor is specifically designed for 3D printer bed leveling, space limited installation, and applications that require thin profiles such as pad ring configurations. This is a dual line device. FSR is a robust polymer thick film (PTF) sensor, and as the force applied to the sensor surface increases, the resistance decreases. The outer diameter of the FSR 404 sensor is 20mm. It has a 5.5mm hole in the middle. The active sensing area of the ring is only 4.35mm wide, but the force sensing capability is enhanced by incorporating a force concentration actuator ring into the component. The standard connection method is to weld the label, but other customized connector options can be provided upon request. Interlink Electronics FSR 404 is part of the single zone force sensing resistor series.