16 pack transparent colored plastic sheets with size 7.8 x 7.8 in/ 20 x 20 cm,reading guide for students | Assorted colors:Trans-Blue,Trans-Red,Trans-Green,Dr. Blue,Trans-Pruple,Trans-Yellow,Trans-Orange,Florescence-Yellow | Made of high light transmission material with light weight steady color temperture and low loss | Color filters used for lighting effects and color correction, involving additive and subtractive color, color mixing, color transmission, absorption and filtering of the different wavelengths of light | Also can help kids reduce reading frustration, improve clarity and eye movement control