I'm going to have to try that out. Another option is Foray brand of ball-point refill at Office Depot. I can't remember the model number, but I saw one Foray refill packet that touted the same qualities of the Fisher pen that fit into a Parker pen (I believe that was the model) & was considerably cheaper than the Fisher pen (the Foray was around $5 + change.) I don't know if it would fit a key chain model of pen, but it wouldn't hurt to experiment. Plus some of us ETS people just put a refill without the pen casing into our emergency kits anyway.

Tim