Just noticed I did not review this item. WOW, I thought resistance training and Bands might have been a gimick. It was the price that got me to get them and test them. Im a believer now. I slam these bad boys into a door, and I get going and don't want to stop. I use them without a door, and entangled in all areas, and have fun with them. They seem very strong, and I do not fear they will snap on me. The threading on the Door jam thingy is coming unraveled a little, but, that would be expected, as I am using them a great deal. Will likely just double stitch them later. All in all, for the price, and how many exercised can be done with these things, I am more than happy. Excellent product.