warm 100g insulation

Shopping for someone else but not sure what to give them

an extra layer of latex foam

4 Degree™ elite fit system for a dialed-in

BIRKENSTOCK BLUE FOOTBED INSOLE MEDIUM Size:40 warm 100g insulationProduct Details: The Blue Footbed utilizes the principle of walking barefoot. It is based on the impression left by a healthy foot in sand, creating a natural environment for your feet. The heel area is cushioned and stabilized thanks to the raised design. This also supports the natural arch of the foot. The Blue Footbed is therefore ideal for anyone who would like to enjoy the unique comfort of BIRKENSTOCK in enclosed shoes made by other brands too.