SwiftPaws home unit and pulleys are made of highly durable material. The tethers that come with the unit are made to break-away for safety. If you find that the tethers are breaking too frequently you can tie a loop for the anchors with the same line you use to create the course (which is provided in the SwiftPaws Home Kit) and can be ordered here (Clicking this link adds the line right to the shopping cart)
We are confident that with proper care of the unit and pulleys (not leaving them out in the weather, etc.) The SwiftPaws home unit should give you years of fun.
We also offer a warranty which you can read about here.