Alchement - Color Change by Light Series, 3D Filament, 1.75mm, 1kg (PLA - White to Purple) - Light-responsive filament changes from natural white, to either purple or blue, depending on the product you order - Capable of changing colors when exposed to sunlight or another UV light source. Weight: 1 kg (2.2lbs) Diameter: 1.75mm (+/- 0.05mm) / Roundness: 1.75mm (+/- 0.03mm)