The P-Switch is an item in New Super Mario Bros. Wii. It is a blue switch with a "P" on it. When you step on it, blocks may turn into coins. It lasts for a short time. As the music gets faster, it tells you it will soon end. P-Switches are rare items. They may appear in Underground levels mostly. When a P-Switch is used it cannot be used again, unless you went in a pipe, exited it, and used it again.