Abstract: A single-ply is folded about a transverse fold line longitudinally offset from a median through the ply and folded about parallel substantially coincident axes to form first, second, third and fourth panels of a mailer assembly. Longitudinally extending lines of perforations define marginal tear strips and transversely extending lines of perforations on the second and third panels adjacent the middle fold line and adjacent a free end of the first panel register with one another to form an end tear strip adjacent the top or bottom of the mailer. Where a return envelope is required, one of the panels has a U-shaped pattern of heat-sealable adhesive to join a pair of registering panels one to the other, with another panel forming a closure flap bearing rewettable adhesive.

Abstract: A single sheet intermediate for a mailer type business form is Z-folded into a reusable mailer having a return envelope. The Z-folding of the intermediate provides three panels of about the same size, and a cut out covered by a transparent patch may be provided in the second panel, the patch covered by a removable outgoing addressee label. The reply address may be printed on the first face of the third panel of the mailer, or on the first face of the first panel on a detachable portion that may be inserted into the return envelope. The return envelope is defined by a generally U-shaped adhesive pattern, open at one side, with a flap having rewettable adhesive at the open side. Removable strips along the side edges of the mailer are held together by permanent adhesive, and are removed when opening the mailer and using the return envelope. The bar coding and the outgoing postage indicia are detached from the mailer when it is opened so that they are not visible on the return envelope.