High-concerned chemical: None - Ensuring a safe and non-toxic testing environment, this vision tester is free from harmful chemicals, making it suitable for users of all ages and providing peace of mind during eye examinations.Size: Vision Tester Tool - Compact and designed for easy handling, this tool is ideal for both professional ophthalmologists and home use. Its size allows for convenient storage and portability, making it a practical choice for mobile eye testing services.Type: 4 dot test Light - Utilizing a four-dot light system, this vision tester provides accurate and reliable results in assessing the eye's ability to perceive depth and color contrast, enhancing diagnostic capabilities.Model Number: Worth 4 Dot Test Light Red Green Glasses Vision Test kit - This specific model includes red and green glasses, enhancing the effectiveness of the dot test by providing a clear distinction in colors, which is crucial for accurate vision assessment.DIY Supplies: Electrical - Designed for easy setup and use, this vision tester kit is perfect for do-it-yourself enthusiasts who are interested in learning more about eye health or conducting personal vision tests at home.Specifications:Item Type: 4 Dot Red Green Light GlassesMaterial: ABS plasticBattery: Built-in rechargeable Lithium-ion batteryColor: As ShownPackage Contents:1* Four Dot Light1* pair of Glasses1* Battery Charger