I can second the comment made by LED Ninja; I carry a clickie Sharpie at work to mark down the expiration dates on the drug boxes and even the "City-issued" ballpoint pens we receive from supply are clickies! Garrity makes a penlight (mentioned above) that runs off of two AAA batteries, and looks like, well, a pen. It has a steel tube body with plastic ends. I simply stuck a 10mm white LED in mine and glued it in place, then used three button cells and an aluminum rod in place of the AAA's to get about 4.5 volts. Perfect for checking pupils in low-light, but hard to get a response with a lot of ambient light around (i.e., back of ambulance w/ overheads lights on). Most of the time, I use my Fenix L1-P and use the sidespill or hotspot to check the pupils-- the latter for our "incooperative" patients... I'd say get her a Fenix L1-P; they use common batteries, are compact, and she can also use it as an "all-around" light without neededing a second hand to switch it on. Since I got my Fenix, I stopped carrying my modified Garrity...