Round seal

A round seal comprising a cylindrical, compressible body having a rectangular through opening having four sides and four corners, fittings at opposite ends of the compressible body, at least four holes extending through the compressible body and the fittings and being located along the four sides of the through opening, a number of screws going through the at least four holes extending through the compressible body and the fittings, and nuts received on the screws,

• wherein the compressible body has first axial length portions and second axial length portions, wherein the first axial length portions are longer than the second axial length portions, and the first axial length portions are located at each of the four corners of the through opening, and the second axial length portions are located at a remainder of the compressible body,
• wherein the at least four holes are located circumferentially between the first axial length portions,
• wherein the fittings are configured to at least partially flatten the first axial length portions during compression of the compressible body by the fittings,
• wherein no first axial length portions are located between the at least four holes and rectangular through opening,
• wherein the compressible body comprises protrusions on at least one side of the compressible body, and
• wherein each of the protrusions extends from one of the corners of the through opening to an outer circumference of the compressible body.