Inner length = foot length + approximately 1cm
Size 21 has an inner length of 13.6cm
Size 22 has an inner length of 14.1cm
Size 23 has an inner length of 14.6cm
Size 25 has an inner length of 15.1cm
Size 26 has an inner length of 15.6cm
Size 27 has an inner length of 16.8cm
Size 28 has an inner length of 17.5cm
Size 29 has an inner length of 18.1cm
Size 30 has an inner length of 18.8cm
Size 31 has an inner length of 19.3cm
Size 32 has an inner length of 19.8cm
Size 33 has an inner length of 20.5cm
Size 34 has an inner length of 21.1cm
Size 35 has an inner length of 21.8cm
Size 36 has an inner length of 22.5cm
Size 37, inner length 23cm
Size 21 has an inner length of 13.6cm
Size 22 has an inner length of 14.1cm
Size 23 has an inner length of 14.6cm
Size 25 has an inner length of 15.1cm
Size 26 has an inner length of 15.6cm
Size 27 has an inner length of 16.8cm
Size 28 has an inner length of 17.5cm
Size 29 has an inner length of 18.1cm
Size 30 has an inner length of 18.8cm
Size 31 has an inner length of 19.3cm
Size 32 has an inner length of 19.8cm
Size 33 has an inner length of 20.5cm
Size 34 has an inner length of 21.1cm
Size 35 has an inner length of 21.8cm
Size 36 has an inner length of 22.5cm
Size 37, inner length 23cm