salipt A Set of Convenient LED Nurse Lighting Tools - Compact Pen Light with LED Pupil Gauge and Hands-Free Clip On Flashlight w

The penlights with pupil gauge and a 5cm-ruler, helpful for you to measure the size of pupil dilation and body parts, the penlights can be powered by 2 pieces AAA batteries with keeping the positive pole + direction of batteries to the pen bulbs.Multiple uses including night shift nursing, camping, hiking, walking, running, dog collar, work belt, construction, emergency light, and more.