The tip of the penetration side of the stoppers could be sharpened or curved.
The vials were sealed with airtight rubber stoppers.
Flasks were stoppered again, and the process repeated until the end of the experiment.
Cylindrical hydrogen sample with a beam stopper located between the incoming ion beam and the hydrogen sample.
If the plunger in the hand-pump becomes stiff and difficult to operate, lubrication of the stopper will restore smooth and easy operation.
This bar appears to be a rolled mat with flaring stoppers at both ends.
Each tube was fitted with a wire mesh stopper at the distal end but was open inside the arena.
The upper end of the cage is closed with a cork stopper.
