Nakaya Decapod Writer Kuro-tamenuri STThe Nakaya Decapod Writer Kuro tamenuri ST fountain pen is a black pen that shows red on the edges of its smooth urushi facets. The Writer model has a clip that fits flush with one of the ten faces and shows off the streamlined shape of the Decapod with its crisp, shape. It is an over all form that can be described by pure geometry except that it is subtly more complex. The ten sided shape has another function. Because it is not round in cross section