StonyLab Glass Stopper Set For 24/40 Glass Joints With Closed Bottom - 5 Pack Review

These come in super handy, continually. Not just for flasks, either - I've had to stopper various female joints due to mishap, poor planning, or just to prevent leakage while switching flasks or between uses of an addition funnel without a stopcock.These stoppers are nice and durable and the penny head means that the diameter is no larger than the joint they fit, so they stay pretty well out of the way. Pretty sure i can use them with 29/*, too, which is nice.