A gas supply member includes a first side opposite a second side and an inner surface defining a first opening extending between the first and second sides. The gas supply member includes a third side orthogonal to the first side, the third side includes a first extension that has a face partially defining the second side, and the first extension includes a first plurality of holes extending through the first extension to the face. The gas supply member includes a fourth side opposite the third side, the fourth side includes a protrusion that has a face partially defining the second side. The gas supply member also includes a baffle disposed adjacent to the inner surface, the baffle includes a first portion extending from the inner surface and a second portion attached to the first portion, and the second portion orthogonal to the first portion and parallel to the third side.