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Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. There are no coupons for this product in Banggood.
Link: Banggood product page
Price: -3 USD
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGTY704CP, BGCuponation10, BGHONEY2110, BG10OFFAFF, BGwhielabel, BG0b82e2, 7bcdf9, BG10OFFAFF1, BGce896a, BG4d9120, BGAlerabatod, 00c906
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi CELESTRON SCTW-102EQ3 Astronomical Telescope.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).