The Ultimate Pen Storage is a versatile storage solution for all pens, including specialized coloring systems. This modular system can be built three different ways to help you fit it into your space, and its perfect for accommodating most pens! Ever since we first launched the Spectrum Noir pens, weve been working on ways to best store them. Due to the nature of dual tip markers, they need to be stored horizontally to ensure even ink flow to both ends. With this in mind, weve developed a versatile storage solution that fits not only Spectrum Noir pens, but also all pens up to 17mm (5/8”) in diameter. Each tray can hold up to 12 pens ? the perfect size to hold 4 full 12 packs of color-themed Spectrum Noir pens ? and they can be stacked as high or as wide as you need. Spectrum Noir is a growing range of alcohol and watercolor mediums which have been designed to suit beginner colorists, students and artists alike. For high-quality, affordable and vivid colors, Spectrum Noir is the brand for you.