I am 59 140lb ordered a size medium. The X straps on the bottoms are ties, its not connected in the back or a clasp. When you tie it, the bow looks a little awkward in my opinion because its  in the middle of your back. The ruching on the front of the ties had the opposite effect I wanted with these bottoms- they make that part of your stomach look like it sticks out FURTHER, not cover it up. If you are trying to hide fat on your hips, this isn't the suit. For me it ended up squeezing between the straps and making it more obvious. The top was also very small compared to the bottoms, like the sizes didn't match.