Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (5.80 USD): BG20236Tool
Coupon (6.41 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
Price history and price alert
Price history (for all/most countries) for 10Pcs Magnetic Nut Driver Set 8mm 5/16 is here.
Price records source(s): Banggood
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You can set price alert (for Banggood).