GP01 Ultra-Miniature Right Angle Pushbuttons NKK Switches GP01 Series Ultra-Miniature Right Angle Pushbuttons combine the cap and plunger into one unit for ease of soldering and cleaning. The GP01 series includes models with black, white, or red caps – or with no cap at all. The pushbuttons feature gold-plated contacts and j bend terminals. These attributes make the GP01 Series more compact, durable, and easier to mount than previous generations.