Samsung has a new deal going for the Galaxy Watch6 in the US, and it's a very, very good one. Basically, if you buy a Galaxy Watch6, in either 40mm or 44mm, with either Bluetooth & Wi-Fi or Bluetooth, Wi-Fi & 4G LTE versions, you can add a second Watch6 to your cart and pay absolutely nothing for it.
So, two for the price of one. "Buy one, get one free" as they say. The expected caveat is that if you select two watches that have different prices, you will pay for the more expensive one and get the cheaper one for free.
All you need to do is go to Samsung's listing page for the Galaxy Watch6, pick the options for your first watch, then scroll down to the "Limited time bundle offers" section and select the third one - "Get a Second Galaxy Watch6 on us". Once you click that you'll be able to configure your second Galaxy Watch6.
If the first watch was the 40mm version, it seems like the second one can only be 40mm, whereas if the first one is 44mm you can pick either 40mm or 44mm for the second (free) one. Note that unfortunately this deal doesn't also apply to the Galaxy Watch6 Classic, for whatever reason.