A pen or a pencil? I have never seen an eyebrow pen. I used to use a pencil but I like the more natural shadow look on my brows, I use the "Sephora" brand brow powder and to keep them in place clear brow mascara. Have you tried "LORAC" ?? If you have a "SEPHORA" near you, you can try just about any kind of brow pencil there is and get help from an employee, they are very sweet and a BIG help.