The Nell by Reformation is a long-sleeve turtleneck knit top that's perfect for layering. The Nell by Reformation is a long-sleeve turtleneck knit top that's perfect for layering. Founded in 2009, Reformation is a revolutionary lifestyle brand combining stylish, vintage-inspired designs with sustainable practices. With each limited-edition collection, the LA-based brand empowers individuals who want to look beautiful and live sustainably.