38 Plates Optometry Color Blindness Test Book with 1~180°(increment:1°)

1~180°(increment:1°)

XXL: Fits waist 140-170cm/55

Your back and shoulders will slowly adjust and you will build muscle memory for the right posture

Portable and lightweight: only 16Ibs

38 Plates Optometry Color Blindness Test Book with 1~180°(increment:1°)Color Blindness Test Book Description A professional test book, which is a simple and accurate method for discovering congenital color blindness and red green blindness, each in two forms, complete and incomplete. It includes four special plates for tests to determine the kind and degree of defect in color vision. Makes use of the peculiarity that in red green blindness, blue and yellow appear remarkably bright compared with red and green. Color