Yosoo Posture Corrector Back Support Belt, Posture Correction, Waist Fixation, Cervicobrachial Syndrome, Shoulder Pain Relief, Forward Head Posture, Kyphosis, Round Back, Adjustable, Easy to Wear, Unisex ▪️Black (L) ▪️L ※ Although the size is L, the website indicates a chest circumference of 89-122, which has a range. I am 160cm tall. I have hardly used it, so there are no scratches or stains, but please refrain from purchasing if you are concerned. ※ No box or instruction manual There was no instruction manual originally, but I put it on by looking at the Amazon site. I think it's easy. Please refer to photo 4.