... proucts have passed ROHS which detected by SGS.6). Strong adhesive can stick to many surface: glass, wood, paper, ... etc.7). Adhesive reaches maximum strength after 24 hours.8). Make sure clean ... such as clothing (sleeve), shoes , bags, safety equipments, Medical supplies (Sphygmomanometer), curtain, outdoor gear, handbag etc. Self-adhesive injection velcro hooks