This is a semi-permanent effect from constant compression on the abdomen area. The more you wear your waist trainer, the faster the results. The truth is anybody can train their waist to be hourglass shaped. Waist training works. It's evidenced in countless testimonials, before and after shots and celebrity endorsements. Waist training is the fastest way to those beautiful curves. If you have issues with your lower back, a waist trimmer gives the extra support you need to sit straight up and reduce the pressure you feel on your back. Giving you that hourglass shape instantly, supports good posture, makes you lose unwanted fat. Trim your waistline to give that flat tummy that you have always wanted! Please note that the zip lock comes in either silver or black