Aproximately a 1/2 inch rounding on any corner. Fantastic for photos, pages, cards, or plastic masks.
From the manufacturer:
This collection of punches are must-have tools for scrapbooking, rubber stamping, card- making and much more! Each corner punch has the sturdy plastic punch lever that the Clever Lever Punches are known for and Available in a variety of themes: each sold separately. Size of punch-outs is approximately 1/2 inch. Punches measure 1-1/4x2x2-3/4in.