The 'Friction Summer Series' is a limited edition inspired by Japanese summer scenes. The 'Friction Ball Slim 0.38 3-color set' features designs like 'sunflower', 'wind chime', 'goldfish', and 'sparkler'. The 3-color set includes a transparent bookmark, both adorned with these summer designs. With a fine ball diameter of 0.38mm, it's ideal for notebooks or planners. The series' theme suggests that while writings made with the pen can be erased, summer memories remain forever. This set captures the essence and emotions of summer.