Abstract: An arrangement for positioning selected compliant seals adjacent the inlet and outlet of a work piece treatment chamber. A plurality of variously dimensioned compliant seals corresponding to work pieces of differing sizes are retained on respective inlet and outlet seal carrier members which, in turn, are mounted adjacent the respective treatment chamber openings. Means are provided to permit the movement and indexing of the carrier members such that any one of the compliant seals may be positioned in operative relationship adjacent the treatment chamber. One such means includes circular carrier members mounting for rotational motion on a shaft. The compliant seals being spaced generally around the perimeter of the carrier member and being selectively positioned by the rotation of the member. Alternatively, a linear carrier member mounted for straight-line movement relative to the treatment chamber openings is contemplated.