Neewer 7"x8"/18 x 20 cm Transparent Color Correction Lighting Gel Filter Set Pack of 6 Gel Sheet for Photo Studio Strobe Flash Light (Red,Blue,Green,Cyan,Yellow,&Magenta) This color filter set consists of 6 pieces 7"x8"/18 x 20 cm gel sheets (red,blue,green,cyan,yellow,&magenta) Made of high light transmission materials with light weight, steady color temperature and low loss. Primary colors:red,blue & green and secondary colors: cyan,yellow,& magenta Color filters are used for experiments involving additive and subtractive color, color mixing, color transmission, absorption and filtering of the different wavelengths of light. Colored gels for lights used in film,video,photo,stage,theater,party,and dj lighting.Note:The Strobe Flash is not included.