Punch Bunch SlimLock Medium Punch - Heart 1inch X1inch - Create party decor, custom cards, scrapbook pages and more. The ergonomic design is easy to use even with consecutively punching. SlimLock lever locks closed when not in use and can be stacked to reduce desk clutter. A design label makes finding a punch and organizing your collection easy. For easy use, the best results and a long life of the punch, use 70lb (100gsm) paper or equivalent weight cardstock.