Reusable Medical Pocket PENLIGHT Pen Flashlight with Pupil Gauge LED Bulb for Nurses, Doctors, and Healthcare Student Interns. Practical doctor/nurse penlight, tail button switch, smooth to use. Pupil gauge and ruler chart on side, offers quick reference. Pocket clip design, easy to carry. This pupil pen light is perfect for examining throat, check ears, eyes or daily use. Bright white light, but not excessive, safe for eyes. Made of aluminum alloy, sturdy. This medical pen torch is small and compact design, easily fits in pocket or clipped onto pockets. Powered by 2 AAA batteries. Order comes with 4 AAA batteries.