Use this easy guide to quickly identify the appropriate rubber stoppers or corks for your glassware & plasticware. Beakers & Flasks | Test Tubes

Size #-holes (size) Top dia. Bottom dia. Fits product
Rubber Stoppers
00 1-hole (3 mm) 15 mm 10 mm Small test tubes
00 2-holes (3 mm) 15 mm 10 mm Small test tubes
0 Solid 17 mm 13 mm Large test tubes
0 1-hole (3 mm) 17 mm 13 mm Large test tubes
0 2-holes (3 mm) 17 mm 13 mm Large test tubes
1 Solid 19 mm 14 mm 50 ml Pyrex flasks
1 1-hole (5 mm) 19 mm 14 mm 50 ml Pyrex flasks
1 2-holes (4 mm) 19 mm 14 mm 50 ml Pyrex flasks
2 Solid 20 mm 16 mm X-large test tubes, 300 mm Graham & 300 mm Liebig Condenser
2 1-hole (3 mm) 20 mm 16 mm X-large test tubes, 300 mm Graham & 300 mm Liebig Condenser
2 2-hole (3 mm) 20 mm 16 mm X-large test tubes, 300 mm Graham & 300 mm Liebig Condenser
3 Solid 24 mm 18 mm 50 ml, 100 ml HST Erlenmeyer flasks, 1-2 L soda bottles
3 1-hole (4 mm) 24 mm 18 mm 50 ml, 100 ml HST Erlenmeyer flasks, 1-2 L soda bottles
3 2-holes (4 mm) 24 mm 18 mm 50 ml, 100 ml HST Erlenmeyer flasks, 1-2 L soda bottles
5 Solid 27 mm 23 mm 125 ml Erlenmeyer flasks
5 1-hole (5 mm) 27 mm 23 mm 125 ml Erlenmeyer flasks
5 2-holes (5 mm) 27 mm 23 mm 125 ml Erlenmeyer flasks
6.5 Solid 34 mm 27 mm 250 ml, 500 ml Erlenmeyer | Florence | Filtering flasks
6.5 1-hole (5 mm) 34 mm 27 mm 250 ml, 500 ml Erlenmeyer | Florence | Filtering flasks
6.5 2-holes (5 mm) 34 mm 27 mm 250 ml, 500 ml Erlenmeyer | Florence | Filtering flasks
8 Solid 41 mm 33 mm 1000 ml HST Erlenmeyer Flasks, 500 ml Pyrex flasks
8 1-hole (5 mm) 41 mm 33 mm 1000 ml HST Erlenmeyer Flasks, 500 ml Pyrex flasks
8 2-holes (5 mm) 41 mm 33 mm 1000 ml HST Erlenmeyer Flasks, 500 ml Pyrex flasks
9 Solid 45 mm 37 mm 2000 ml HST Erlenmeyer Flask
9 1-hole (5 mm) 45 mm 37 mm 2000 ml HST Erlenmeyer Flask
9 2-holes (5 mm) 45 mm 37 mm 2000 ml HST Erlenmeyer Flask
10 Solid 49 mm 42 mm Fits many vacuum bottles, 2000 ml HST Erlenmeyer Flask
10 1-hole (5 mm) 49 mm 42 mm Fits many vacuum bottles, 2000 ml HST Erlenmeyer Flask
10 2-holes (5 mm) 49 mm 42 mm Fits many vacuum bottles, 2000 ml HST Erlenmeyer Flask
Cork Stoppers
2 Solid (use borer) 13 mm 9 mm Small test tubes
4 Solid (use borer) 16 mm 12 mm Large test tubes
6 Solid (use borer) 19 mm 14 mm X-large test tubes, 50 ml Pyrex flasks
9 Solid (use borer) 24 mm 18 mm 50 ml, 100 ml HST Erlenmeyer flasks, 1-2 L soda bottles
14 Solid (use borer) 32 mm 25 mm 250 ml HST Erlenmeyer flasks, 500 ml Erlenmeyer flasks