This pattern uses mainly basic Single Crochet stitches. It is stitched in the round so there are no seams. It is also stitched in one continuous pattern to reduce the need to fasten off, weave in ends and start a new piece (except for the optional ID/Credit Card pocket). You can use any yarn you choose, just adjust your hook size for the yarn and the dimensions to fit the phone size. It’s a great stash buster pattern.