It's more like fleece than a knit sweater. The inside is made of a warm material. Size is 100cm. The button at the neckline can be opened. The cuffs and hem are made of rubber material. The rubber is firm and hasn't stretched. It's cool and cute! How about it for this time of year? I've worn it about twice, and the condition is relatively clean. However, it is a used item, so please understand. Thank you very much! (^-^)