4cm Ruler & Pupil GaugeDesigned with pupil gauge and 4cm-ruler on the side of this penlight, which can help doctors or nurses measure the pupil dilation and length accurately and quickly when using SEVENKA medical pen lights, bring great convenience to the daily work of doctors or nurses. Two Light Modes----White & Warm LightFreely select white or warm light mode as you need. Bright white light is great for checking nose, mouth, ears or as a flashlight for lighting in the dark. Soft warm light is ideal for checking eyes. Pocket Size & Convenient to UseThis compact penlight comes with a pen cap that can stop it from accidentally turning on in your pocket and running out, also prevent damage caused by falling. Take off the cap before use, then press its button on the top 3 times to switch between white light, warm light and off. USB-C Rechargeable Medical Pen LightNo more wasting money on buying batteries! SEVENKA Mini LED penlights has built-in rechargeable battery, you can recharge it at anytime with the included USB-C charging cable via usb socket, power bank, computer, etc. Tiny blue indicator light will show up when charging and it will disappear when fully charged. Note: Please fully recharge this LED pen lights before first use. Lightweight Penlights with Pocket Clip & Durable MaterialWeighing only 18g/0.6oz with metal pocket clip, SEVENKA nursing pen lights are convenient to carry. Premium aluminum alloy material makes these led pen flashlights possible to be more durable and long-life using. Best Gift & What You GotIf your friends, families, relatives or neighbors are nurses, doctors paramedic, pediatrician, emergency medical technician or nursing students, this pen light is must an ideal gift choice! Package includes: 2 Pen Lights with 2 short (30cm/11.8in.) USB-C charging cables.