[Pack of 4 Outer Diameter: 3.3 inches (83 mm) | Convex Outer Diameter: 3.0 inches (7]
[Pack of 2 Outer Diameter 3.1 inches (78 mm) | Convex Outer Diameter 2.7 inches (6]
[Pack of 4 Outer Diameter 3.5 inches (90 mm) | Convex Outer Diameter 3.2 inches (8]