Every SUNNUM frame begins as a single block of premium High-Density acetate — our signature blacks sourced from Mazzucchelli 1849 in Italy, one of the world's most respected acetate houses, and our coloured variants precision-selected from leading manufacturers. CR-39 lenses complete the picture: a lightweight optical resin long trusted for its clarity, depth of tint, and exceptional visual precision. Nothing superfluous. Every material chosen for a reason.