As others have said, CLEAR is only in IAH Terminal A which you could use if not checking bags and have secured your boarding pass before arriving—just hop on the train. I love Clear and use it at Hobby all the time. As some have said, Terminal C is a security mess... between PreCheck being closed in the evenings and Premier Access lines being merged with the regular security lines in the evening.... well I find UA Terminal C security at IAH to be a frustrating mess and makes me more likely to buy my next ticket out of Hobby—now my primary airport. It seems that once upon a time Clear was at Terminal D and now it’s gone there too.