Footbed material: EVA
EVA (ethylene vinyl acetate) is a high-quality, very light, elastic material with very good cushioning. As a result, it smooths out slight irregularities in the floor and ensures that every step is softly cushioned.
Fitting: Birkenstocks are fairly generous on their sizing and also remember a sandal fits the foot differently to a closed in shoe. Over the years we have found alot of customers men and women tend to go down one continental size to their usual sizing. They have recently started to state UK sizes on the box but we would still say that you are best to size up using the continental size. We find this is more accurate. Remember you want your foot to fit in the footbed nicely without toes hanging over the edge of the sandal or conversely gaps around the foot. There are two width fittings narrow and standard. Both are very accommodating as the strapwork is adjustable. Narrow tends to be more aimed for ladies and standard lends itself a better fit for mens. Obviously if you have had Birkenstocks before just base the sizing on the previous continental sizing, even with years of wear, this usually still remains visible on the footbed.