a balance be struck with the plug 56 being spaced a sufficient distance from the apertures 80 to provide a small cavity between the apertures 80 and the bag 14 located slightly distal to the apertures 80 is an optional locking flange 106 shown in fig7 only which mates with the notch 55 in the inner wall 50 of the adapter 38 the locking flange 106 resists the probe 66 and engaged plug 56 being inadvertently pulled from the interior of the bag 14 the invention allows the bag 14 to be re sealed by the plug 56 for example if one wish to change containers when the bag 14 were only partially empty the probe 66 would simply be withdrawn from the bore 52 thereby replacing the plug 56 in its sealing position as shown in fig2 with the bag being re sealed without spillage or introduction of air it is important that the snap connection between the probe 66 and the plug 56 be more difficult to release than the snap connection between the plug 56 and the inner wall 50 of the adapter 38 is to effect the bore 52 is relatively easy to re seal because the side 61 of the plug 56 approaches the rib 57 of the adapter 38 at an obtuse angle tending toward horizontal this allows the ridge 62 to.