Many work environments are cold, and yet we must have our fingers free to use keyboards, etc. These wrist warmers are super simple to make, and yet more than just a short or long tube.
The model yarn, Paton's SWS is discontinued; Paton's website recommends their Classic Wool Roving and their Shetlands as substitutes.
Anything that matches its recommended gauge should work: 17 stitches & 21 rows = 4 inches on US9
I think the color play is what makes these items pop, so look for something varigated.
6 rows & 4 stitches = 1 inch