A sealing element for a rotating control device includes an elastomeric body having a central bore for sealing against a pipe passing therethrough. The elastomeric body has an upper portion which is internally reinforced with a frame and a lower portion formed with a plurality of protrusions. The radial protrusions provide columnar support to the lower portion permitting the lower portion to resist centrifugal and frictional forces against the lower portion during drilling and other operations. The sealing element may be used to form an assembly with reusable parts for connecting the sealing element to a mandrel of a rotating control device.