The pen barrel has a built-in metal counterweight of approximately 4.4g, which increases the weight creates a low-centre-of-gravity feel to the pen body, and enhances the writing feel. The solid color of the pen body makes it comfortable to hold and visually clean. The use of high-quality nibs, non-inking, smoother writing, the use of high-capacity refills, writing range, and replaceable refills, are economical and practical.