Martin Yale MP80 Master Hole Punch, 9/32" Hole Diameter, Punches up To 80 Sheets of 20 Pound Bond Paper, Handle Locks Down, Adjustable Paper Guide Powers through up to 80 sheets of 20 lb bond paper Spring-assist mechanism and oversized handle for easier punching of stacks Pre-set to punch 9/32 Inches diameter holes to fit a standard 3-ring binder Handle locks down for storage and safety Flip up guards on each punch head ensure safe use and assist in alignment