6: Inner circumference 52mm. inner diameter 16.5mm.
7: Inner circumference 54.7mm. inner diameter 17.3mm.
8: Inner circumference 57mm. inner diameter 18.2mm.
9: Inner circumference 60mm. inner diameter 19mm.
10: Inner circumference 62.4mm. inner diameter 19.8mm.
11: Inner circumference 65mm. inner diameter 20.6mm.
12: Inner circumference 67.5mm. inner diameter 21.5mm.
13: Inner circumference 70mm. inner diameter 22mm.
14: Inner circumference 72mm. inner diameter 22.8mm.
