ATM you can buy Electric Heated Socks Croppable for 7.99 USD (in Banggood). Basically copy coupon, view price history or create e-mail price alert. You probably want to know what is the best price?
Latest price update (UTC time):
Banggood (7.99 USD)
Banggood warehouse is located in China. So I have checked for active coupons (all category coupons and old ones), but there was no working coupon in Banggood. Price? Looks like a good price to me (average is 8.39 USD).
Link: Banggood product page
Price: 7.99 USD
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGTYHS03
(I don’t think these’re gonna work, but you can try ’em out anyway)
Aliexpress
Here are coupons that you can use.
Price history and price alert
Here is price history (for all/most countries) for Electric Heated Socks Croppable.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).