These versatile PTFE stoppers are able to fit all ground joints with either a handle head or flat penny head design. Great for volumetric flasks and separatory funnels, PTFE avoids freezing in ground zone. Handle head design enables easy removal from flasks even if the ground joint freezes. Stoppers come solid or hollow with a standard taper.

Stopper Sizing:
Joints have a two part number such as standard taper 24/40 with 24 being the approximate diameter in mm at the large end of the taper and 40 being the axial length of the stopper's taper in mm.

Flasks have a single number that represents the approximate diameter in mm at the top of the neck of the flask.