Snap On Rubber Stoppers

Natural red or grey rubber Snap-On Stoppers. This design provides maximum sealing for vials with a blow-back glass finish, which is a small ridge in the interior of the vial's neck. The snap-on rubber stopper locks into the blow-back ridge, providing a tight seal and keeping the snap-on rubber stopper from backing out. This style is not recommended for vials with a straight-walled finish. The blow-back feature is typically found in vials from North American manufacturers.