PET bottle coupler (PCO-1881)
A replacement cap for two bottles joined into one container or a tornado toy. The thread matches the PCO-1881 standard, so it screws onto store bottles; the two sockets join two bottles neck to neck. Print it in PETG so it flexes onto the neck instead of cracking, and add 0.1 mm of clearance if your brand runs tight.

2D preview
Customize (configurator with these values)
Files are generated on request from the live generator; free, no account.
Specifications
| Neck | PCO-1881 (24.94 mm, 2.7 mm pitch) |
|---|---|
| Style | two sockets back to back |
| Grip | knurled |
| Seal | none (dry seal on the neck lip) |
| Clearance | 0.5 mm, adjustable |
Printing
- Prints top-down as exported, threads up: no supports.
- PETG over PLA: it flexes onto the neck instead of cracking; 0.16 mm layers smooth the fine pitch.
- Too tight: regenerate with +0.1 mm clearance, necks vary by brand.
More pet bottle caps
- Spare PET bottle cap (PCO-1881)
- Two-bottle PET coupler (PCO-1881)
- Spare cap for PET bottles (PCO-1881)
- PET bottle cap with hanging loop (PCO-1881)
- Spare cap for older PET bottles (PCO-1810)
- PET bottle cap with loop (PCO-1810)
- 38 mm juice and milk bottle cap
- 38 mm bottle cap with hanging loop
- All pet bottle caps · set your own dimensions in the PET Cap Generator