Flex Boot (Regular) size 150 converted to Cavallo Trek

Sizing across brands only works through the millimetre band, never the number. Flex Boot (Regular) and Cavallo Trek both publish in millimetres, so a Flex Boot (Regular) 150 (hoof length 150 to 160 mm) is matched by finding the Cavallo Trek size that covers the same length.

Flex fits within plus or minus 5 mm of the listed width and no longer than the listed length. A naturally round or upright hoof wants the Flex Wide, whose length and width match, rather than the Regular.

Cavallo sizes on length, then you pick sole width. If your width is 6 mm or more under your length, choose the Slim sole in that size; otherwise the Regular sole.