Most clients think it's a special tyre valve caps, or tyre valve indicator cap. But as a kind of tire pressure monitoring system, one of its features is of the LED alert indicating the lower tyre pressure status.
There is a tyre pressure valve inside the tyre pressure monitor which is playing a very important role in the TPMS functions. It senses the tyre pressure up and down, over inflated or under inflated. Its accuracy is very high comparing to the market LED TPMS products: + - 1psi. Most manufactured devices are in a range of accuracy: + - 1.0 psi, But some devices are of a larger range of + - 1.5 psi. The pressure valves integrated into the LED tpms are manufactured in a very strict and high tech working process with the good support of pressing mould making technology. Most mould making suppliers are not able to produce such higher accuracy in size and arc radians. The most key point factor is the arc radians. The accuracy of arc radians determines the accuracy of tyre pressure detection. High accuracy in arc radians of tyre pressure valves supports the trucks, buses; higher accuracy in arc radians of tyre pressure valves supports the LED blinking alert for 4psi drop, which suits cars, light duty vehicles; highest accuracy in arc radians of tyre pressure valves supports the LED blinking alert for 1psi drop, which suits most vehicles: bicycles, motorcycles, cars, trucks, buses, OTR tires. Precision degree determines the use range of TPMS functions. Better tyre pressure valves can detect more tyres and vehicles.
So it's the core technique in the LED tpms industry. Also the technical level of pressing mould making determines the defective rate. Rare mould making factories are able to produce such high precision pressing mould for the special need of tire pressure monitoring system. If you find a not good manufacturer, they will spend your money and produce a bad pressing mould which is not able to stamp out the very precision tyre pressure valves. Thus your thousands of dollars are gone, a useless mould left you. Thus you see, the LED TPMS are more like the mechanical devices than electronic digital products comparing to the market tire pressure monitoring system which uses the integrated circuit and wireless technology to detect the tyre pressure and temperature and transmit them onto the display.