Size 26, inner length 16.2cmSize 27, inner length 17.2cmSize 28, inner length 17.8cmSize 29, inner length 18.5cmSize 30, inner length 19cmSize 31, inner length 19.5cmSize 32, inner length 20.2cmSize 33, inner length 20.8cmSize 34, inner length 21.5cmSize 35, inner length 22cmSize 36, inner length 22.5cmSize 37, inner length 23cmSize 38, inner length 23.5cmSize 39, inner length 24cmSize 40, inner length 24.5cm