Abstract: Apparatus for supplying moisture to an envelope, having a body portion and a flap portion, the apparatus including, a substantially solid-rectangle-shaped pad made of a material capable of upwardly transferring fluid by capillary action, a device for supplying fluid to the pad, the fluid supplying device including a source of supply of fluid, the fluid supplying device including an elongate well having an elongate substantially rectangularly-shaped base wall, the well including a fluid inlet tube depending from the base wall and removably connected in fluid flow communication with the fluid supply source, the well including a pair of elongate substantially rectangularly-shaped and oppositely-spaced side walls, the well including a pair of substantially rectangularly-shaped and oppositely-spaced end walls extending between the side walls, the side and end walls extending upwardly from the base wall, the well including a plurality of upright posts located at spaced intervals longitudinally of the length of the