The Inka Mobile is designed to go where you go, write where you need it to write, and stay where you want it to stay so it's always conveniently at hand. Made of durable nylon and carbon fiber that's tough, lightweight, and corrosion-resistant, one end of the Inka Mobile features a carabiner clip that securely anchors to a key ring, zipper pull, or nearly any loop or D-ring, so you can always know where the pen is when you need it. Release the pen from the clip with a couple of quick twists-its replaceable pressurized cartridge contains blue waterproof ink that writes smoothly and consistently in extreme temperatures, upside-down, at any altitude - even underwater. And to add to its versatility, the cap at the opposite end of the Inka Mobile opens to reveal an easily accessible touch-screen stylus - perfect for everything from quick notes to business presentations. With its compact size, durable construction, reliable performance, and replaceable pressurized blue ink cartridge, the Inka Mobile is designed to be everything you need in a pen and stylus.