Features 1. 180 SHEETS CAPACITY - These wire binding rings are suitable for A4 size paper, with a binding diameter of 19mm (3/4") and can hold up to 180 sheets of paper. 2. Metal Inner Wire - The inside of these double loop binding wires is made of sturdy and durable metal wire, which is sturdy and durable, allowing you to organize documents easily and store them for a long time. 3. Nylon Coating: these A4 paper wire binding spines adopt nylon external coating, with shiny surfaces, wear-resistant and scratch-resistant, with a long service life. 4. PERFECT SIZE - Each double loop wire spine is 3/4 inch in diameter and 0.8mm thick. Each spine has a 3:1 pitch and 34 double rings, 360 degree rotation is supported. 5. Binding Wire: Use these binding bobbins with double loop thread to bind important documents, files, or reports for upcoming presentations or projects. Compatible with most cable bundling systems (3:1 pitch and 34 hole mode). Specification: Item Type: Double Loop Cable Binding Spines Material: iron, nylon Binding Diameter: 19mm/0.75" (3/4") Binding capacity: 180 sheets (A4, 70g) Number of teeth: 34 teeth Ratio: 3:1 How to use: take out and install to use Packing list: 50 x Double Loop Wire Binding Spines Package List 50 x Double Loop Wire Binding Spines