Item Type: Worth 4 dot light Material: ABS Battery: button battery(not included) Product Function: Wear red and green glasses to observe 4 dot light, and use the aura of complementary colors to separate the 2 eyes, so as to determine whether the 2 eyes have monocular inhibition and fuse vision function under the condition of separation.1Avoid Detection Deviation: Worth 4 dot light is pure in red and green, which can be completely filtered. The red and green colors are complementary, effectively avoiding detection deviation. 2Clinical Test: Professional 4 dot binocular test is a clinical test for eye suppression and amblyopia, which has great advantage to your eyesight and eye health. 3Improve Clarity: You can improve the visual clarity by using worth 4 light test, which is able to make your eyes more comfortable, and have no bad influence on you. 4Adjustable Pupil Distance: Binocular 4 dot light pupil distance is able to be adjusted up to 43?83mm, which is able to be used by adults and children. 5Function: You can wear red and green glasses to observe 4 dot light test, and judge whether there is monocular inhibition and fusion vision function in both eyes when they are separated. 1 x Red Green Flip Tool 1 x Worth 4 Dot Light 1 x Manual 1 x Storage Box