Clear Design for Easy Use: The transparent design allows you to see the color and amount of remaining ink, making it convenient to use and refill Convenient Refillable Design: These watercolor brush pens can be easily refilled with your favorite watercolor or ink, saving you time and money Ideal for Various Art Projects: Suitable for painting, calligraphy, sketching, and more, these refillable watercolor pens are a must-have for any artist Sturdy Materials: Made from sturdy plastics and nylon, these watercolor brushes excellent painting performance and Convenient and Portable: This set of 36 watercolor brush pens is designed for artists . and portable, these brushes can easily be transported in a carry case or backpack, making them an excellent choice for outdoor painting sessions or travel.