Abstract: A generally loose-fitting tubular sheath article, such as a condom, which has a closed distal end and an open proximal end which is bounded by a knitted material that bears compressively on the sheathed member to provide retention. The knitted material may be in the form of a band which is affixed to the sheath by everting a portion of the sheath material at the proximal end over the knitted material and attaching the sheath material to itself, thereby creating a toroidal enclosure in which the knitted material is disposed. Constriction of the sheathed member is minimized by the knitted material which provides a large surface area for retentive contact.

Abstract: Method and apparatus for filtering air admitted to the cab of a vehicle, particularly one which operates in a severe environment, comprises a pre-cleaner unit and a source of low pressure which continuously removes separated particles from the pre-cleaner unit. The source of low pressure is a venturi which is operated by the flow of air passing through the radiator of the vehicle's engine.

Abstract: A headless form tie rod and associated fastener that contacts the form tie at two spaced points. The tie rod provides a cylindrical body with plural spaced areas protruding in one dimension and flattened in the other dimension. The principal fastening structure provides a wedge type device that releasably fastens the rod in a form structure at two spaced points. A species of fastener provides releasable fastening by means of a pivotable lever. Spacing washers releasably positionable on the form ties maintain forms in spaced relationship.