Item Type: 4 Dot Light Visual Test Kit Material: ABS Batteries: 2 x AA batteries (Not Included) Function: Wear red and green glasses to observe the four-hole lamp, and use the phenomena of color complementation to separate the two eyes, so as to judge whether there is simultaneous vision and syncretic visual function of monocular inhibition in the two eyes in the case of separation Package List 1 x 4 Dot Light 1 x Detachable Optical Flipper 1 x Red Lens 1 x Green Lens 1 x Manual 1 x Storage Box 1Accurate Detection: The red and green colors are pure and can be completely filtered. The red and green colors are complementary, effectively avoiding detection deviation. 2Wide Range Of Applications: 4 dot light test kit is used for clinical tests of eye suppression and amblyopia, and it can determine the type of color vision disorder. 3Check Color Blindness: Optical flipper design is simple but very practical to use, helping you test for color blindness and color weakness, with adjustable interpupillary distance. 4Portable Design: Visual function test tools help with visual clarity. Small and lightweight, comes with storage box, easy to carry, suitable for optometry places, optical shops, etc. 5ABS Material: Red and green lens can be easily installed on optical flipper, simple operation. Adopts ABS material, firm and sturdy, stable and durable for use.