Assorted Rubber Stopper Set — 30-Piece, Sizes #000–#12, Solid & 1-Hole

A complete rubber stopper set is the connective tissue of a chemistry lab — every flask, tube, and bottle needs one, and having the right size on hand is the difference between a working experiment and a frustrating delay.

Natural rubber resists distortion and cold flow, maintaining a gas-tight seal over repeated insertions. The set covers the full range from tiny 16mm test tubes (#000) to 1000mL Erlenmeyer flasks (#12), with both solid stoppers (for sealing) and single-hole stoppers (for thermometers, gas inlets, or tubing). All stoppers are autoclave-compatible at 121°C.

• 30 stoppers — 15 solid + 15 single-hole; sizes #000 through #12
• Natural rubber — autoclave compatible (121°C); resists dilute acids/bases
• 1-hole stoppers accept 4–8mm glass or PTFE tubing
• Stored in reusable zipper case; sizing chart included

Every purchase directly funds independent physics research at the Golden Physics Project.