Thanks for the link, that's very useful. I found the passage "Marketing through a general retail outlet or by mail order to the general public with a simple disclaimer, such as "For Business Use Only," is not sufficient to qualify as Class A. Instead, all marketing (advertising, sale and distribution) must be restricted by the marketer to users in a commercial, industrial, or business environment" quite interesting. I've wondered how much manufacturers can wriggle out of their statutory obligations to consumers by adding the disclaimer "For Business Use Only". Sounds like these ASIC miners should be going for FCC certification/verification in the US. I would imagine that the same is probably true in the EU too. Do you know how aggressively are these rules enforced?