I have checked all old coupons and price is $6.99 for SONOFF SNZB-04-ZB Wireless Door/Window Sensor (in Banggood). Get coupons, create price alert or check price history out! Best price?
Battery: 3V(CR2450);, Sensor: 47X27X13.5mm, Wireless connection: Zigbee3.0;, Material: PC;, Magnet: 32X15.6X13mm, Dimension:
Latest coupon code price check (UTC time):
Banggood ($6.99)
Banggood warehouse is located in China. There are no coupons available at this moment in Banggood. But wait a sec… Is it a good price? Cool, average is $8.26, so current price is lower!
Link: Banggood product page
Price: $6.99
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGSONOFF15, BGSNZB04, BgcLuBofErtA10, BGSONOFF16, BGSTHO15, BGHONEY2110, BGSHOM15, BG7fca50, 13f142, BGSHE15, 6GSGIT, BGSmart6, 8Couponsde, MVC8SPRING, 8BGwbg2204, 2203ActiesNL, tRaDetRaCKeR, 8wEbgaInS5, pROMo8cuPoN, BGJUNEGSG9, BG15Sonoff, TTSUMMER8, Cuponation9, 9OFFSUMMER, BG8745ca, BG9ded82
(I don’t think these’re gonna work, but you can try ’em out anyway)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – SONOFF SNZB-04-ZB Wireless Door/Window Sensor [EU] ($-3)
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 SONOFF SNZB-04-ZB Wireless Door/Window Sensor 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)).