VELCRO Brand heavy duty hook & loop fasteners are aggressive moulded hook and woven loop closure system with a superior water resistant rubber based adhesive for indoor and outdoor use | The adhesive will achieve 80% bond strength in about an hour and full strength in 30 hours | The VELCRO Brand? heavy duty hook & loop range offers 50% more holding power than the everyday general product range | UV and weather resistant (-18 to 80 degC) for semi-Permanent jobs | Designed to adhere to rough surfaces including concrete and certain types of brick | Superior holding power on smooth surfaces, including plastic, indoors and outdoors