The Lip Service Knotched Throwing Rib for Rims has multiple uses for finishing rims. Each end features a notch of a different size and angle for perfectly shaped rims. The beveled edges make it easier for the tool to glide along the clay without catching or creating friction. The smoother design makes surfaces more stable and helps the clay hold its form on the edges of the pot. The 90 degree corner is a great replacement for trimming and cleaning.