The shoes are tabed with Europe size, please refer to the Inner Length:
Size 4.5 = UK 2 =Europe 34, Inner Length 22cm=8.66IN
Size 5 = UK 2.5 = Europe 35, Inner Length 22.5cm = 8.86IN
Size 6 = UK 3.5 = Europe 36, Inner Length 23.0cm = 9.06IN
Size 7 = UK 4.5 = Europe 37, Inner Length 23.5cm = 9.25IN
Size 7.5 = UK 5 = Europe 38, Inner Length 24.0cm = 9.45IN
Size 8 = UK 5.5 = Europe 39, Inner Length 24.5cm = 9.65IN
Size 8.5 = UK 6 = Europe 40, Inner Length 25.0cm = 9.84IN
Considering the Height Increasing Insole, you may need to choose a bigger size for Wide Feet or High-arch, if you couldn't ensure which size to choose, please tell me your foot length, then I will check which size fit you well;
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