Many mills now offer the standard 5.6 oz. The heavier the weight, the thicker the fabric, the more the shirt costs. Sweatshirts starat at approximately 7.5 oz. It's called a midweight. The difference is in the brushing of the back of the fabric to provide the fleecy look and feel.
Sweatshirts come in a wide array of weights and fabric content.
Down Under Design makes all these weights available so you can choose the shirts that's just right for your needs and your wallet. Cotton is the big seller these days. Nobody today wants to iron a T-shirt. They are also more stain resistent. Cotton is over-whelmingly the shirt of choice.