The inner liner is used to adjust the riding helmet to the size and shape of your head. For optimum comfort and fit. The KEP riding hats come in 2 shell sizes with 2 different types of liners, one for the oval shaped head and one for the rounder shaped head. The round shaped liner is usually the most common one but if riding helmets often press across your forehead, then the oval shaped liner is probably better for you.

M-sizes are 52, 53, 54, 55, 56, 57, 58
L-sizes are 59, 60, 61, 62