Allow me to briefly introduce our cutting edge TPMS - Tyredog 1000A-X, 1. The smallest TPMS in the market - Dia.20mm x L 22mm; weight:11gm 2. Easy to install - user needs only screw the sensors onto the valve stems to take place the valve caps. 3. FCC approval, Comply with part 15, class B rules. 4. United States Patent No. US 6993962 B1.