Amazfit is a popular wearables brand with its own e-store that serves several regions, the US included. It is currently running a promotion that offers a free second strap with every purchase of its latest GTS 2 and GTR 2 series of smartwatches. These bands normally cost about US$20, meaning this might be a good chance to get two in different colors for a limited time.
https://www.notebookcheck.net/Amazfit-offers-a-free-strap-with-every-GTS-2-2e-or-GTR2-2e-sold-via-its-own-site.526813.0.html
You call that a deal? You can get a watch 3 or active 2 for almost half the price and like 8 bands for free. Used to be like 16 bands but they are running out of stock.
Probably Samsung is clearance them for the 4.