Features 1、Avoid Deviation: 4 dot glasses has pure red and green colors, which can be completely filtered and complement red and green, effectively avoiding detection deviation. 2、Flashlight Handle: The flashlight in this set of optometry tools has an anti slip design, which is easy to hold and not easy to slip off when using. 3、Main Function: For the clinical examination of visual suppression and amblyopia, it can determine the type of color vision disorder of the patient. 4、Storage Case: With a portable storage box, you can organize and store your accessories, so you can easily carry them around. 5、Excellent Material: Made of hard material, lightweight and virtually unbreakable. Include the red green glasses, and instructions manual. Specification Item Type: 4 Dot Red Green Light Glasses Material: ABS Battery: 3 x Battery (not include) Product Function: 1. Wearing red and green glasses to observe the four dot light, the use of color complementarity of this situation, the separation of the two eyes. 2. To determine whether there is visual fusion dysfunction in the two eyes in the case of separation of monocular inhibition at the same time. Package List 1 x Four Dot Light 1 x Glasses 1 x Storage Box 1 x Instruction Manual