How to Chain Multiple AMS 2 Pro and AMS HT Units (Up to 24 or 25 Colors)
Each AMS 2 Pro has two 6-pin ports on the back so you can daisy-chain units in series using the new 6-pin cable (2.5 mm step height). H2D and H2S printers support up to 4 AMS 2 Pro units and 8 AMS HT units simultaneously (24 AMS slots, plus 1 external spool on the H2D’s second nozzle for 25 colors). The P2S supports up to 4 AMS 2 Pro and 4 AMS HT units (20 slots), while X1 and P1 printers support up to 4 AMS units (16 slots). Last checked October 25, 2026.
One of the biggest upgrades introduced with the AMS 2 Pro is expanded daisy-chaining: instead of the old 16-spool ceiling on every machine, newer Bambu Lab printers can combine AMS 2 Pro (4 slots each) and AMS HT (1 slot each) for up to 24 or 25 filaments. Here are the exact connection rules from Bambu Lab’s multi-model compatibility guide as of October 25, 2026.
Maximum AMS chaining capacity by printer model
| Printer Model | Max AMS 2 Pro Units | Max AMS HT Units | Total AMS Slots / Colors | Required PTFE Merging Hardware |
|---|---|---|---|---|
| H2D / H2C (Dual-Nozzle) | 4 units (16 slots) | 8 units (8 slots) | 24 AMS slots + 1 external spool = 25 colors | Built-in buffer + 4-in-1 PTFE Adapter(s) when connecting 3+ units |
| H2S (Single-Nozzle) | 4 units (16 slots) | 8 units (8 slots) | 24 slots (24 colors) | Built-in buffer + 4-in-1 PTFE Adapter(s) |
| P2S | 4 units (16 slots) | 4 units (4 slots) | 20 slots (20 colors) | P2S Filament Buffer + 4-in-1 PTFE Adapter(s) for 3+ units |
| X1 / P1 Series | Up to 4 units | Check firmware notes | 16 slots (16 colors) | AMS Hub (Method 1) or Filament Buffer + 4-in-1 PTFE Adapter (Method 2) |
Four hardware rules you must follow when daisy-chaining
- Always use the new 6-pin bus cable (2.5 mm step height): Every AMS 2 Pro has two 6-pin ports on the back. Connect Unit 1 to the printer/buffer, then daisy-chain Unit 2 into the spare 6-pin port on the back of Unit 1 using the new 2.5 mm step cable. Never use a 1st-gen AMS 6-pin cable (1.1 mm step) on an AMS 2 Pro or AMS HT, or communication will drop.
- Never reverse the Buffer and 4-in-1 PTFE Adapter: Bambu Lab’s wiki warns: “A buffer must sit between the printer and every AMS. When using multiple AMS units, install the 4-in-1 PTFE adapter between the AMS and the buffer; never reverse the connection.”
- Do not use the spare 6-pin port on the P2S Buffer for a second AMS chain: On the P2S buffer, only one 6-pin port is for chaining AMS units; the second port is reserved for accessories like time-lapse kits. Always daisy-chain AMS 2 Pro units back-to-back instead.
- Keep PTFE curves gentle and units level: Keep AMS units on the same level as the printer where possible and avoid tight bends in the PTFE path to prevent feeding drag.