AMS 2 Pro PTFE Tube Length Guide (370 mm, 500 mm, 550 mm, 600 mm) & Routing Rules
On X1 and P1 printers, the short 370 mm PTFE tube always connects the right side of the filament buffer to the printer’s rear coupler (routed UNDER the spool holder, never over it). The longer tube from the AMS 2 Pro outlet to the left side of the buffer is listed as 500 mm, 550 mm, or 600 mm depending on the wiki page and printer model. Always keep curves gentle and push tubes past the pneumatic lock. Last checked October 25, 2026.
If you are replacing worn PTFE tubing or installing an upgrade kit, you may notice that Bambu Lab’s own pages list several different tube lengths (10 cm, 370 mm, 500 mm, 550 mm, and 600 mm). This reference table brings together every PTFE tube measurement mentioned across Bambu Lab’s AMS 2 Pro documentation as of October 25, 2026.
Every AMS 2 Pro PTFE tube length explained
| Tube Length | Where It Connects | Which Bambu Page Lists It |
|---|---|---|
| 370 mm | From the right port of the Filament Buffer to the PTFE coupler on the back of the X1/P1 printer | P1S Install Wiki, Intro Guide, UK Upgrade Kit 1[cite: 5, 8] |
| 550 mm (or 500 mm) | From the AMS 2 Pro rear filament outlet to the left port of the Filament Buffer on X1/P1 printers | X1/P1 Drying Wiki & UK Upgrade Kit 1 say 550 mm; P1S Install Wiki says 500 mm[cite: 8] |
| 600 mm | From the AMS 2 Pro rear filament outlet to the left inlet of the buffer (listed in multi-model / newer printer buffer section) | AMS 2 Pro Intro & Connection Guide |
| 10 cm (100 mm) | From the output port of the 4-in-1 PTFE Tube Adapter into the input of the Filament Buffer when merging multiple AMS units | AMS 2 Pro Intro & Connection Guide |
Four PTFE routing mistakes that cause feeding errors
- Routing the tube OVER the spool holder on a P1S/X1C: Bambu Lab’s P1S install guide specifically instructs you to route the 370 mm PTFE tube under the external spool holder bracket, not over it, to prevent a sharp downward bend into the extruder[cite: 8].
- Compressing the Filament Buffer spring: When inserting the 370 mm tube into the right side of the buffer and the coupler, check that the internal buffer slider spring moves freely and is not pinned or compressed[cite: 8].
- Leaving the release tape or not seating the tube fully: Remove any shipping tape on the AMS 2 Pro outlet, push the PTFE tube in as far as it goes, and tug lightly to confirm the pneumatic teeth locked onto the tube[cite: 8].
- Failing to trim worn tube ends: Bambu Lab’s connection guide notes that PTFE tube ends wear out over time from abrasive or high-speed feeding, which can cause filament to catch and snap inside the path. Periodically inspect the cut ends and trim or replace worn tubes.