I've made my own since I was in junior high school(and made a fair amount of spending money in HS opening cars that people locked their keys in at the bar next door to a friend's tattoo shop). They're not technically illegal in CO, but might get an add on charge of "Possession of burglary tools" if you happen to get arrested for something else. I can easily justify my possession of them as a working mechanic. I've used commercially available ones, and wasn't impressed by either their capability or durability.