Mares X-Stream Fins X-stream Comfort, X-ceptional Efficiency • New foot pocket. No parachute effect • Next generation OPB • New blade construction for less turbulence The X-stream performance, comfort & lightweight design are the incredible result of sixty passionate years at the service of diving. The X-stream is truly a leap into the future, & changes forever how we envision the creation of a fi n. More than 2 years of resources, experiments & testing & four Mares patents all concentrated in one unique product.