From FibreMood:
Calvin is everything you would expect from a cosy jumper. We used a basic jumper as our template, but added a few special details For example, additional seams sewn on the front give the jumper a fascinating graphic design feel. The bottom cuff sports a mix of ribbed trim and sweatshirt fabric. If colour blocking is your thing, just cut the different parts in different colours.
Fabric advice
Make the Calvin jumper out of sweatshirt fabric, French Terry or neoprene. Cut the collar, wrist trim and cuffs from rib-knit trim. The cuff fabric is elastic, but also maintains its shape.