The following knife blades can be used:
2 knives with a blade length of up to 25.6 cm and blade width of 5.0 cm
2 knives with a blade length of up to 24.6 cm and blade width of 4.7 cm
2 knives with a blade length of up to 22.6 cm and blade width of 3.7 cm
2 knives with a blade length of up to 19.6 cm and blade width of 2.4 cm