No teeth, Adjustable clamp. Parallel pliers don't pinch the rings they clamp the rings. this will reduce slipping Rings Max Recommended Wire Thickness (*See Notes Above): Stainless and Titanium (SS/TI): 12gCopper (CU): 12gBronze and Brass (BZ/BJR): 12gAluminum (anodized AA and bright AB): 12g Minimum Recommended Size (*See Notes Above): 22g