Twing Folding Endurance Tester Schopper method PD-2 model
The device is designed to determine the double-fold strength of high-strength papers up to 0.25 mm thick using the Schopper method. It is especially recommended for security papers and banknotes where there is a direct correlation between double-fold strength and the paper's actual strength.
ISO 5626 – TAPPI T423 – SCAN P17