How to convert camel's shoe size?

General conversion formula: (Ou Ma+10)×5= China shoe size (that is, millimeters).

China Ou Ma Shoe Size (mm)

34 - 220

35 - 225

36 - 230

37 - 235

38 - 240

39 - 245

40 - 250

4 1 - 255

42 - 260

43 - 265

44 - 270

Due to the appearance characteristics and materials of hiking shoes, I feel that other shoes will be bigger.