Color Pink/Blue, Weight/Size 150g/D64* H84mm, Heating Mode, High temperature 50 ° C, Input/Output DC5V 2A/ DC5V 1A, Material Aluminum alloy, Battery Lithium polymer battery 3600mAh, 2 Modes: Medium temperature 42 ° C, ABS, silicone.
Basically copy coupon, view price history or create e-mail price alert. What is the best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($29.44): BGHB218
2. ($32.56): BG00c906
put item in your cart and apply coupon code there after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): BGBFAFF2019, BGHW2, BGCare2, vipupgrade8, 0e7f33, BGHB20, BGSD52147, 13f142, BGCuponation10, BGHONEY2110, BG10OFFAFF, BGwhielabel, BG10OFFAFF1, BANGGOODSD, BGHealth06, 00c906, BGHealth10D, 2022ACTIESNL
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Jeffbona Hand Warmer 3600mAh. The lowest price was: $16.99.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).