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Click here… to search for KCASA KC-TP500 Pen Cooking Thermometer on Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (14.87 USD): BG1efeb0
Coupon (15.03 USD): Terence
Coupon (15.03 USD): 2203ActiesNL
(CouponsFromChina.com tip: coupon code has to be applied in shop’s 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): BGKCTP500, AFfbG10, BGBFAFF2019, BGCITYADS2019, BGVDay10%off, BGHOMEG12, BGKCASAFB, bGhOnEy10, BGKCAGHF, BGdragonBoat, BGSS10%SW, BGAFF10OFF, BGHome15%, BGKCASA20%, BgcLuBofErtA10, BGHONEY2110, BG10OFFAFF, BGwhielabel, 13f142, BG10OFFAFF1, BANGGOODSD, BGAlerabat1
(probably won’t work, but you can try them out)
Price history and price alert
Price history (for all/most countries) for KCASA KC-TP500 Pen Cooking Thermometer is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).