Karhu have been established since 1916, used by some of Finland's most legendary runners in the early days. Karhu shoes have won Olympic medals to Boston Marathons and everything in between.

The Synchron Classic features a new compression molded EVA midsole, which is current in most modern running shoes. The dual density construction remains true to the original version from the early 1990s. The upper materials have been improved to premium pigskin suede from synthetic overlays, but the mesh appearance remains original to the era.

To modernize the silhouette, Karhu incorporates the Air Cushion technology, both visible and functional in the outsole. Most importantly, Karhu keeps the unique Synchron lacing construction, which served as a way to tighten the forefoot upon repeated use.