Ring Inductive Proximity Sensor (30mm Hole Diameter) Category_Grove (Arduino)/Grove Gas Qvar (electric charge variation detection)

Qvar (electric charge variation detection) is embedded in the LSM6DSV16X for user interface functions like tap

* Driver/Receiver Enable connected to RTS line of FT232RL

The digital CMOSens® technology integrates two sensors and readout circuitry on one single chip

The I/O and voltage rails are all broken out to a pair of breadboard-compatible headers

this would be a good choice

Ring Inductive Proximity Sensor (30mm Hole Diameter) Category_Grove (Arduino)/Grove Gas Qvar (electric charge variation detection)These Inductive Ring Proximity sensors are designed to detect metal objects entering or passing through the ring. They operate on a 6 36V power supply and offer NPN output. The sensor features less than 1ms response time, high accuracy and stable performance, which could work well even in the detection of fast moving small metal objects. It comes with onboard LED for indicating detection status(light up when metal object detected) and sensitivity