Lego Writing System Clikits Heart pen The Lego writing system is the first of its kind. The only pen you connect and build. Mix and match the colorful clikits elements to create fun, new designs every time you write. The Heart pen includes: a create your own pen and 16 clikits elements. The pen has a soft grip and uses a replaceable ink cartridge. The barrel of the pen is pink and grip on the pen is pink. The pen has black ink. Just turn the grip to write. The clikits elements are pink, magenta, and green hearts and circles. Design your own heart pen. The clikits elements are interchangeable with clikits elements from other Lego Clikits pens.