Size 20 mm: Inner Diameter: Approx.19.70mm Outer 21mm Diameter: Approx.24mm Height:Approx.4.93mm Thickness:Approx.2.4mm Size 24mm: Inner Diameter: 24mm Outer Diameter: 27mm Height: 5mm Size 26mm: Inner Diameter: Approx.26mm Outer Diameter: Approx.31.8mm Height:Approx.4.6mm Thickness:Approx.1.8mm Size 30mm: Inner Diameter: Approx.30mm Outer Diameter: Approx.34mm Height:Approx.6.3mm Thickness:Approx.2.4mm Size 32mm: Inner Diameter: Approx.32mm Outer Diameter: Approx.35.9mm Height:Approx.5.4mm Thickness:Approx.2.27mm Size 40mm: Inner Diameter: 40.6mm Outer Diameter: 45mm Height: 7mm