Purchased at Fred Meyer (similar to Walmart, but bigger). I have to say I hated regular glue on patches. They were messy, time consuming, and although they worked, it was a hassle to prep everything. These save a few of the steps. Primarily, you just prep the surface by sanding, then affix the patch. That simple. I've used them on my 700x23c tubes at 130 psi with no problems.