According to my DB the lowest price is $35.09 for Wireless TPMS Tire Pressure Monitor Car Tire Pressure Monitoring System (in Banggood). Go down and check coupons out. Remember to check price history if it is available. Let’s see what best price is ATM.
Latest coupon code price check (UTC time):
Wireless TPMS Tire Pressure Monitor Car Tire Pressure Monitoring System Solar Charging Car Tire Pressure Sensor Real-Time Monitoring – Internal
Banggood ($35.09)
Banggood warehouse is located in China. The question is – is it a good price? Maybe there’re no more promotions for this item, because current price is higher than average (which is equal $29.48) One coupon is available. Cool!
Link: Banggood product page
Price without coupon: $38.99
1. ($35.09): BGAMMT03
apply code in your basket (cart) after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGSCM11
(there’s a little possibility that old coupon will work)
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Price history and price alert
Price history (for all/most countries) for Wireless TPMS Tire Pressure Monitor Car Tire Pressure Monitoring System is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).