Larger Eggbot Pen Arm

When you built your Eggbot ( http://egg-bot.com ), were you disappointed that the default pen arm wasn't large enough to accept the ubiquitous fine point Sharpie marker? I know I was (especially since I had just bought a pack specifically for my new Eggbot).

This model is a replacement pen arm for the Eggbot, designed to accept Sharpie fine point markers (of course, anything smaller in diameter will fit too!).