Side zipper. There are pockets on both sides. It's a size 0, so it's labeled as a size S, but the actual waist measurement is 70cm. Total length is 43cm (both measurements are approximate, so please allow for some error). The pockets seem to act as a moderate weight, so the flare doesn't spread out as much as it appears when laid flat. I've worn it 3-4 times. Instant purchase is also OK. Thank you.