Abstract: An improved sleeve valve for use in a flexible paper bag which is adapted to package granular products. The sleeve is mounted in the open mouth located in a corner of the flexible bag and adapted to receive the filler spout of a product-dispensing mechanism. The sleeve valve comprises a tubular plastic sleeve which is adhered to both the open mouth of the bag and to a paper backing panel. The sleeve valve is adhered to the backing panel by three glue bars which are spaced from each other and spaced inwardly from the mouth of the sleeve valve. The rear portion of the paper backing panel is slit lengthwise along its longitudinal center and the rear portion of the plastic sleeve valve adjacent the backing panel is also slit lengthwise along its longitudinal center in substantial juxtaposition with the slit in the paper backing panel.