1、90 SHEET CAPACITY: The spiral binding coil has a diameter of 12.7mm (1/2in) and can hold up to 90 sheets of paper (A4, 70g), allowing for easy addition or removal of pages. 2、4:1 PITCH AND 48 TEETH: The spiral binding coil is designed with a 4:1 pitch and 48 teeths, making it compatible with any binding machine that punches 4 holes per inch. 3、CONVENIENT PACK SIZE: Each box contains 100 spiral binding coils, ensuring long term productivity for all your binding projects. You can easily bind your papers and have enough supply for a prolonged period. 4、360 DEGREE ROTATION: The spiral binding coil allows for a 360 degree page flipping and rotating feature, making it easier to read and allowing your bound projects to lay flat. 5、IDEAL FOR LETTER SIZE: These 48 teeth binding coils are perfect for letter sized papers (8.5 inches x 11 inches), and the length can be easily cut with scissors according to individual requirements. They are great for engineering documents, business projects, office documents, and university presentations.