Abstract: A retention system may comprise a bracket, a bar system, a seal and a bonded washer. The bracket may have a first portion and a second portion. The first portion and the second portion may be operatively coupled together at an angle ?. The bracket may also have a texture. The bracket may define a mounting surface. The bar system may comprise a bar installable in the bracket. The seal may be installable in the bracket and disposed beneath the mounting surface. The bonded washer may be installable on and compressible against the mounting surface.

Abstract: An apparatus for covering an exterior opening in a roof is disclosed. The apparatus includes a hollow conical element defining an inner volume, the conical element having a first opening on a wide end and a second opening on a narrow end. The apparatus further includes a planar element surrounding an outer brim of the first opening, wherein the planar element accepts a fastener for fastening the apparatus to the roof. The apparatus further includes at least one louver covering the second opening and at least one screen located within the inner volume of the conical element, wherein the at least one screen is fastened to an inner surface of the conical element.