PYREX® Glass Straight Bore Stopcocks with [ST] PTFE Stopper, Corning®
Straight Bore Stopcock, Pyrex®. The standard taper PTFE plug fits into a micro-finish barrel. Freezing problems are reduced and greasing is eliminated. The very fine threads on the plug and nut let you "feel" the position of the plug. Sidearm seals are heavy and strong for greater durability and easier handling.