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Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. Only one coupon available!
Link: Banggood product page
Coupon (20.66 USD): elec
(CouponsFromChina.com tip: 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
Price history and price alert
Here is price history (for all/most countries) for SONOFF G1 GPRS Remote Control Switch.
Price records source(s): Gearbest, Banggood
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You can set price alert (for Banggood).