Tangent ELM-Tk (ELM-Tk) Element Tk Control Panel. With today’s multi-purposing work stations, where desk space is at a premium, having a fully featured panel that is compact, fully featured and stylish enough to match its surroundings is a must. But, you’d expect that having a compact design means having to compromise ergonomics, features and control size. With the Element range, there is no compromise.