There is nothing like performance testing to confirm whether you have a good product and service. For the past fours years a 10 pound red sand bag has been used as a tire or car stop holding back a 1991 Volvo station wagon driven by teenagers. Almost every day for 4 years this sand bag has been stopping the car while being parked in a residential garage. It is showing some wear and tear from salt, debris, and tire discoloration. The bag has not split out at the sewn seams and the Velcro closure has stayed secure. View a photo album of the 10# sand bag in operation.