STOPPERS #4-13 are a crag climber's staple - with curved 3 point contact for better security while placed in their narrow aspect. The #1-3 are are flat sided for maximum surface area contact, weigh practically nothing and are a god send for hairline cracks and pin scars you may not even see from the belay. If you choose a STOPPER and it's smaller then the intended slot, rotate it 90 degrees and place it sideways. These placements are enhanced by a transverse taper to better "seat" in slightly wider cracks and flares. STOPPERS undergo an extensive amount of tumbling to round off any sharp edges making them easy to place and also clean. Every STOPPER is pull tested to 1/2 of its rated strength. Color anodised for easy size recognition. Assembled in China from US components.