What is What is drop, in millimetres??

Drop is the height difference between the heel and the forefoot of a shoe, measured in millimetres. A high drop tilts the foot forward, a flat profile lands you level, and switching between them changes load on the calves and Achilles. The spread here is wide: BeLenka Europe sits at 0 mm, runnershub at 7 mm, Mizuno and PUMA at 8 mm and 8 mm, and Nike highest at 10 mm. Useful rule: keep a drop close to the one your current shoes use.