Laboratory rubber stoppers #0–#13 and wine corks — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/rubber-stoppers-and-corks/  (CC BY 4.0)
Basis: Standard US laboratory stopper sizes (top and bottom diameters, 25 mm tall, taper ~1:8); wine corks #9 (Ø24 × 44/49)
Catalog version: 2026-10-20

Sizes: see table below
- Stopper number → top/bottom diameter (mm): #0 17/13, #1 19/15, #2 20/16, #3 24/18, #4 26/20, #5 27/23, #6 32/26, #6½ 34/27, #7 37/30, #8 41/33, #9 45/37, #10 50/42, #11 56/48, #12 64/54, #13 68/58. All 25 mm tall; one- and two-hole versions take 5–7 mm glass tube.
- Pick the stopper whose mid-diameter is 1 mm over the opening: 16 mm test tube → #0; 20 mm → #2; 25 mm → #4/#5; 28 mm soda-bottle neck → #6; 70 mm jar mouth → #13 is too small, use a printed disc.
- Corks: #9 natural wine cork Ø24 × 44 mm (49 long for aged wines), compressible to Ø21; silicone stoppers survive 230 °C, natural rubber 80 °C. A cork drilled 3 mm is the cheapest displacer-rod gland for a test-tube engine.

number  top_mm  bottom_mm  height_mm  fits_opening_mm
#0  17  13  25  14–16
#1  19  15  25  16–18
#2  20  16  25  17–19
#3  24  18  25  19–23
#4  26  20  25  21–25
#5  27  23  25  24–26
#6  32  26  25  27–31
#6.5  34  27  25  28–33
#7  37  30  25  31–36
#8  41  33  25  34–40
#9  45  37  25  38–44
#10  50  42  25  43–49
#11  56  48  25  49–55
#12  64  54  25  55–63
#13  68  58  25  59–67
#9 cork  24  24  44 / 49  22–23

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Wikipedia: Bung — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Bung
- Wikipedia: Cork (material) — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Cork_(material)
- Long Earth Society: Engine builds (videos and write-ups) — web, video — LES site — https://longearthsociety.com/engineering/

Free files (CC BY 4.0, Xem Studio; STEP + STL, 17 parts): https://xemstudio.com/files/hardware/rubber-stoppers-and-corks/index.json
API: https://xemstudio.com/api/geometry?object=rubber-stoppers-and-corks