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Click here… to search for GEPRC GEP-GR1408 Brushless Motor 3500KV on Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (14.55 USD): Cuponation9
Coupon (14.71 USD): TTSUMMER8
(CouponsFromChina.com tip: you should apply the coupon 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): TTxBG10, BGGR1408, BGGEPDrone, BGGEPPart, Parts8, AFfbG10, BGMPB2020, BGAFF10OFF, bGhOnEy10, BG1408EDX, BGdragonBoat, BGSS10%SW, bgshOOp10, BGRC902, BgoFErTaSchInA10, BgcLuBofErtA10, BGCuponation10, BGDAVIS, BGHONEY2110, BGGAL8, BGJON8, BGRCParts8, Tabby20, BG1efeb0, 8Couponsde, MVC8SPRING, 8BGwbg2204, tRaDetRaCKeR, 8wEbgaInS5, pROMo8cuPoN, BG8RCToy, BGJUNEGSG9, BGRCT10
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Price history (for all/most countries) for GEPRC GEP-GR1408 Brushless Motor 3500KV is here.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).