Ribs are made of food-grade, rust resistant stainless steel. They do not flex.
Rib measures approx. 3 3/4" tall by 4 3/4" wide.
For an 8 oz cocktail, use 1 lb of clay. Throw a 4 1/2" tall, 1 1/2" wide cylinder. Also try Wanda as a planter profile rib.