🌚Vintage Long Cropped Tank

I got this from my mom 15+ years ago and she had it for a long time before that. This thing is from the 80s or 90s but it is in amazing condition! No tag with size or fabric info, but I suspect it is either small or medium. Fabric is likely synthetic, but it has a really smooth feel and has some stiffness to it...maybe nylon. Wish I could keep but after 2 kids my boobs would hang out the bottom 😜