1、Avoidance Of Deviation: Red green glasses is pure in color and can be completely filtered. Red and green colors complement each other, effectively avoiding detection deviation. 2、Test: 4 dot binocular vision light set is able to be used for clinical test of eye suppression and amblyopia, it is a good helper for doctors to test. 3、Long Term Use: 4 dot vision test light has a built in large capacity battery, which has a service life of 2‑3 years and is able to be recharged 500 times. 4、Function: 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. 5、Applicable Scenes: 4 dot vision test light is very small and can be carried around, whether you are at home or out of the house, it is very suitable for optometry places. 1 x 4 Dot Light1 x Manual1 x Red Green Glasses1 x USB Cable Item Type: 4 Light test red green glassesMaterial: ABSBattery: 2000mAh Li ion battery(built in)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.