This pattern by Kristy Hunter was made on a 3/4" 22 peg CinDWood loom and is available in a loom+epattern + loom bundle for February 2021. It can also be done on a 3/4" 20 for smaller legwarmers or 3/4" 24 for larger.
Giving a 5 star rating because I love these looms! I have the 7/16 afghan loom, and think this hat loom will be great. I like the Cindwood looms better than the KBs.