Features： 1、Bright Lighting: Illuminate your way with the bright and efficient acrylic bulb, providing focused light while saving energy and ensuring durability. 2、Portable Design: The included clip allows for easy portability, conveniently attaching the pen style flashlight to pockets, collars, or other accessible areas for quick and convenient use. 3、Easy On Off Operation: Rear end alloy button switch ensures simple and reliable operation, allowing for easy turning on and off of the single light mode. 4、Versatile With Built In Ruler: Take advantage of the engraved 50mm scale ruler on the flashlight body, providing a quick and convenient measuring tool for everyday use. 5、Enhance Examinations: Flashlight body is designed with a pupil comparison chart, assisting in clinical examinations and routine checks, making it a valuable tool for medical professionals. 6、Physical Reversal Technology: The battery spring contacts are physically reversed to prevent oxidation and poor contact and to improve efficiency. Specification： Item Type: Medical Pen Light Material: Aluminum alloy, resin Light Colour: Yellow light Batteries: 2pcs AAA batteries, shipped without batteries Package List： 1 x Medical Pen Light