This high-quality ink refill is compatible with a range of HPQ pens, including models 61, 62, 63, 950, 951, 564, 920, and 901. It comes in a sleek black color, with cyan, yellow, magenta, and green accents. This ink refill is perfect for anyone who wants to add a pop of color to their writing, while maintaining a professional and legible appearance. It is easy to install and use, providing a smooth and consistent writing experience. This ink refill is ideal for collectors, students, and anyone who enjoys writing with style.