With the addition of iconic Harley-Davidson designs and the Hex-O-Matic, the Retro 1951 ballpoint pen offering has more than doubled. All Retro 1951 ballpoint pens are a click-top for point deployment. A Retro 1951 ballpoint pen will accept an extremely broad selection of ballpoint refill technologies: standard ballpoint ink, GEL ballpoint ink, Liquid ballpoint ink as well as the Easy Flow technology from Schmidt. Some ballpoint ink choices come in as many as eight colors. Only the Harley-Davidson Flathead requires a different refill, choose from a wide selection of Monteverde mini ballpoint refills.