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Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. We have found one coupon for this product!
Link: Banggood product page
Coupon (28.10 USD): BG589b2e
(CouponsFromChina.com tip: just apply this code in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BG2f7b9a, BG717000, BGe7038b
(there’s a little possibility that old coupon will work)
Price history and price alert
Check out price history chart (for all/most countries) for BSP-D3 Bluetooth 5.0 Wireless Type-C Phone Gamepad.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).