penlight for stethoscope work really well and it is very helpful to have the pupil measure on the side of the penlight.
Imprinted Pupil gauge helps determine pupil size at a glance
led have the different colors and penlight for stethoscope needs to measure pupil size its a great light
medical led penlight with the compact and colorful design the pupil gauge and the effective but not harsh LED light
Included replaceable AAA batteries, Penlight sise: 13.5cm (5.3")Length x 1.3cm(0.51")diameter, LED color: white light and pen color: red or silver.