Microsoft's official Xbox controllers, whether from the Series or One generations, are an awesome gamepad for PC gaming too. By default though, your options for connecting the controller are Bluetooth (on later models) or a wired USB connection - rather than the low-latency 2.4GHz wireless you get on Xbox consoles, which requires Microsoft's $25 Wireless Adapter for Windows. That adapter is down to $18 at Newegg today, and is well worth picking up while it's discounted.
As well as giving you an easy and low-latency way to connect Xbox controllers, the same proprietary Xbox Wireless connection is also used for some Xbox headsets, joysticks and other peripherals. If your peripheral connects to the Xbox without needing to insert a USB wireless adapter, then it'll also work on PC with this adapter - which is a handy way to extend the functionality of products that you may have already picked up for Xbox.
The official adapter is actually fairly hard to find in my experience - the Microsoft Store is often out of stock and the few first-party adapters on retailers like Amazon tend to be incredibly expensive for some reason. There are a fair few third-party equivalents at around the same price, but as I haven't tested them I can't speak to their quality. I have used the official model, both the larger 'original' model and its smaller successor, and they've always worked reliably for me.
The functional differences between the two models, old and new, are purely down to the form factor - the newer model is 66% the size of the old model, so it's more convenient if you're using it with a gaming laptop on the go, or on a case where your USB ports are closely clustered. Otherwise though, you should expect the same performance and feature set from both adapters.
That just about does it for now, so stay tuned for more deals as we discover them and feel free to let me know in the comments if this deal was useful. Cheers!