Explora Hoof Boots size E4 converted to Flex Boot (Regular)

Sizing across brands only works through the millimetre band, never the number. Explora Hoof Boots and Flex Boot (Regular) both publish in millimetres, so a Explora Hoof Boots E4 (hoof length 135 to 145 mm) is matched by finding the Flex Boot (Regular) size that covers the same length.

Do not read the plain number and the E number as one size. An Explora 2 and an E2 share a length band but the E2 is the narrower boot; pick the line by your measured width.

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.