GBC 12mm Silk White Thermal Binding Covers - Pack of 25 Designed for the GBC ThermaBind system, Standard Thermal Binding Covers give a stylish 'perfect bound' look to documents. They combine a transparent PVC front to display the title page clearly and a white silk - finish back, forming a totally secure spine with permanently bound pages. Features: - Feature a 150 micron, transparent PVC front cover for easy reading of the title page - Perfect for use within the office - Come with a Silk White 240gsm back for extra rigidity - Sheet capacity: 120 80gsm - Page size: A4