Abstract: An adjustable deckle is provided for use in papermaking machinery to be positioned between the ends of adjacent wear surfaces to facilitate prevention of loss of vacuum applied to the wear surfaces in operation of the machinery. The deckle includes an elongated member having a pair of opposing elongated front and rear faces, a pair of elongated top and bottom faces and a pair of end faces. The front face has a configuration conforming with the configuration of an adjacent edge of one wear surface when the deckle is inserted between two wear surfaces. The rear face has a recess therein and a resilient strip is mounted in the recess. A shiftable element is also mounted in the recess by engagement between surfaces of the element and surfaces of the elongated member. The shiftable element has a portion exposed through an opening in the rear face of the elongated member.