10mm Plastic Spiral Coil Binding Supplies 12" 100/PK Black 3/8" 68 Sheets cap - Walmart.com
20PCS 30-hole Notebook Binding Spiral Ring Book Plastic Single Wire Ring Coil Binding Supplies DIY Cut Out Spiral Binding Coil
20pcs 30-hole Notebook Binding Spiral Ring Book Plastic Single Wire Ring Single Coil Binding Supplies Spiral Binding Coil - Binding Combs & Spines - AliExpress
28mm (1-1/8-inch) Binding Coils - 4:1 Pitch - 12 Inches Long - Pre-Sized to Fit Letter-Sized Paper (100/box - up to 260 sheets) - 334128