Prevents colour distortion due to super-transparent and colourless construction. The cover glasses for hemocytometers have a refractive index. - Excellent flatness. - High spectral transmission. - Optimum resistance to chemical attack. - Low levels of inclusions, striae, bubbles, streaks etc. - Thickness: 0.4 mm. Prevents colour distortion due to super-transparent and colourless construction. The cover glasses for hemocytometers have a refractive index. - Excellent flatness. - High spectral transmission. - Optimum resistance to chemical attack. - Low levels of inclusions, striae, bubbles, streaks etc. - Thickness: 0.4 mm.