YONO Set 6 Pastel (BULLET)YONO Set 6 Pastel (BULLET) YONO = You Only Need One The Marabu YONO Marker is an opaque acrylic marker pen that works on almost any surface. The marker is suitable for light and dark surfaces, and contains high quality ink that is water based, lightfast and has very little odour. Variable 1. 5 3 mm Bullet tip. The tips can be removed from the shaft of the pen for cleaning, and can also be replaced. These markers are suitable for use on most surfaces