Write-on dividers are made of durable plastic for frequent reference in your letter-size binders. Customize entire divider using a ballpoint pen or pencil. To reuse, just erase and write on again. Three-hole punched dividers are translucent and multicolored. Bigger tabs provide 50 percent more writing space than standard tabs.Write-on dividers are made of durable plastic for frequent reference in your letter-size binders. Customize entire divider using a ballpoint pen or pencil. To reuse, just erase and write on again. Three-hole punched dividers are translucent and multicolored. Bigger tabs provide 50 percent more writing space than standard tabs.