I bought this used and wore it a few times. The chest pocket can be accessed from the side. There is no Japanese size notation, but it's EUR: S, USA: S, and MEX: 26. I think it's equivalent to a Japanese M size, but it's oversized so you can wear it loosely. Length: 74cm Width: 59cm Sleeve length: 54cm Shoulder width: 47cm Please note that these are amateur measurements, so there may be some errors. Please check the photos and understand that this is a used item before purchasing. Also, please be aware of any folding wrinkles that may occur during shipping. I do not accept price negotiations, but I occasionally review the price. Instant purchase OK! We will ship within 24 hours via anonymous delivery.