Abstract: Disclosed is a closure member for insulating, sealing, waterproofing and otherwise protecting an object from the elements. The closure member is of integral, one-piece construction, is of heat-shrinkable material, has a main body for enveloping the object and easily hand-assembled hooks, formed from material-sandwiched, angled and articulated inserts, interfoldable to define a joint and form thereby an enveloping tubular member. The hooks have on their ends small projections defining detents that are mechanically imbeddable for positive joint closure and seal, while affording a wide range of alignment in the interfolded and sandwiched assembly of the hook.