Fullness99 via eBay offers the Tire Pressure Monitor Valve Stem Cap 4-Pack for $ 2.15 with free shipping. These caps fit on any standard size tire valve stem and provide visual alerts of each tire’s pressure.

LINK – eBay : www.ebay.com/itm/191274405471?rmvSB=true

I got it last time and does it jobs well. Quality is cheap though.

Note: This ships from China with an estimated delivery time of three to seven weeks.