Inumbra is an umbrella by Dirk Wynants for Extremis. Stainless Steel Pole and Hi-tech Polyester Fabric.Inumbra is a unique umbrella for its essential and its aesthetics. The parasol opens and closes by means of a separate handle. All technical parts that open and close the screen are above the inumbra's UV resistant fabric and consequently are not visible when seated under the parasol. Inumbra has been submitted to wind-tunnel testing at the Von Karman Institute. Although the parasol can withstand wind speeds up to 8 on the Beaufort scale, it is advisable to close it sooner (from wind speed 6 is the rule of thumb).