Sherrill Mud Tools : Small Bowl Rib :YELLOW Soft Flex
Red - VERY SOFT
(Great for compressing slabs, burnishing rims, chamois, and handbuilding.)
Yellow - SOFT FLEX
(Perfect for smoothing, burnishing, porcelain, throwing, and handbuilding.)
Green - MEDIUM FLEX
(Great for compressing bottoms, burnishing, trim marks, throwing, and handbuilding.)
Blue - FIRM FLEX
(Still Flexible but Stiffer. Great for high burnish and throwing large work)