Is this tied to the account or to the device?
is this for PC or Mac
Single use licenses are usually device specific.
Hopefully, a Woot staffer will verify this on Monday.
Per Google AI
No, you cannot use the Mac version of Office Home & Business 2021 on a PC; you must purchase the Windows version for a PC. While Office Home & Business 2021 includes versions of the same applications (Word, Excel, PowerPoint, Outlook) for both Windows and Mac, these are separate licenses that cannot be transferred between operating systems. Each license is for either one PC or one Mac, not both.
Here’s why and what you can do:
Platform-Specific Licenses:
A one-time purchase license for Office Home & Business 2021 is tied to either a Windows PC or a Mac. You cannot use the Mac installation media on a PC, or vice versa.
Separate Purchases:
To use Office on a PC, you need to purchase the Windows version of Office Home & Business 2021.
One Device Limit:
The license for Office 2021 is for one PC or one Mac, not for both simultaneously.
Transferring the License:
You can transfer the license to another computer of the same type (e.g., from an old Mac to a new Mac, or an old PC to a new PC) by removing it from the old computer first.
For a PC and a Mac:
If you need to use Office on both a PC and a Mac, you will need to purchase two separate licenses: one for the Windows PC and one for the Mac.
These are tied to an account. You can unregister it from one Mac and install it on another if you want. Instructions are on the Microsoft site. But you can’t run it on two devices at once.
@welshcustoms2 it says it’s for Mac right in the title. 
(Oh I see the specs are generic for both operating systems. It’s a goof.)