I am assuming you had a tummy tuck (the question title didn't say but I saw you asked another question about TT)?If the surgery was a TT with liposuction, and you are 4.5 WEEKS out (not MONTHS), then the answer is YES, it can cause damage. Wearing a tight or heavy band across a healing area of liposuction at only 4 weeks can cause permanent grooves. This is why most plastic surgeons recommend uniform compression for up to 6 weeks postop. It does help with swelling mostly, but it also keeps uniformity in the healing region. While the chances of problems are less at 4 weeks than at 4 days, I would recommend wearing the belt over some form of more rigid compression such as an abdominal binder (or at least Under Armour) underneath your clothing. One it will help keep your contour more uniform, two it won't be any more bulky than your bulletproof vest, and three it will decrease the likelihood of a permanent deformity. Hope that helps!CDK