21 yards inner length 13.5cm

14cm inside size 22

14.5cm inside size 23

24 yards inner length 15cm

15.5cm inside size 25

16cm inside size 26

Within 27 yards, 16.5cm long

28 yards inner length 17.1cm

29 yards inner length 17.7cm

The inner length of size 30 is 18.3cm