Debbie, I use a 45 degree blade. No special housing needed; it's basically the same size as the blades sold by Cricut, just a slightly different angle and (maybe?) a somewhat better quality. I do know that they last a lot longer than the Cricut blades.
I just got an email, and he said that his labels were defective and the addresses faded during shipping. I'm being patient and I'm not getting upset. He said that he was resending them. I haven't really scrapped all summer, so what's the rush!