The Tempo Universal plate supports both ANSI and ISO layouts. ANSI layout is the standard layout used in the United States and many other countries while ISO layout is the standard layout used in many European countries.
For plate materials, bottom-out firmness and acoustics are considerations of preference. In our experience, softer materials may help reduce finger fatigue for long typing sessions, while firmer materials may provide a more responsive feel. The order of plate materials from soft to firm is POM, FR4, Carbon Fiber, Aluminum, Copper.