Master features the same orthopedic footbed as Viva and Holiday which prevents and relieves the symptoms of splayfoot. Master is recommended for those who suffer from Plantar Fasciitis. However, MasterÆs footbed is covered by a thick cushion of compressed Jute/Felt. This comfortable layer of non-abrasive, absorbent cushioning makes Master especially adapted for work boots, leisure boots and athletic shoes. An extra soft heel pad relieves pressure & impact on the heel. Master has a latex-free charcoal filter to prevent odor. Master has antibacterial treatment and extremely hygienic for your feet. The felt is also great for winter to keep you warm.