Blue Ribbed Mockneck Shirt

Thrifted from a shop in Melbourne, Australia a while back. Sleeveless ribbed mockneck with slits up the side. Same on the front and back. Great for layering. No stains, tears, etc. No label either (no clue what the fabric is, but guessing something synthetic). No size, but it has a lot of stretch so I'd almost call it one size -- I normally wear a M in tops though, and this fits well.