Stan's Flow MK4 Rim - 27.5, Disc, Black, 32HDurability and an almost uncanny feeling of control on the trail have made Flow rims the preferred choice of multiple Red Bull Rampage riders, and today's Flow goes even further. The Flow MK4's reinforced spoke bed, combined with the offset drilling of the asymmetric design, builds into an incredibly durable wheel that brings added confidence to every ride. Unlike many rims, the BST Asymmetric shape is designed to equalize resistance to dents and tire