How to Identify Your Reusable Filament Spool
Updated September 22, 2026
Before checking whether a refill fits, you need your spool's exact brand, model, and generation - manufacturers change spool design over time, and a refill documented for one generation is not automatically documented for another. Here's what SpoolNook has been able to confirm about telling generations apart, by brand.
Bambu Lab
SpoolNook has only found one current Bambu Lab reusable spool design documented (ABS+PC construction). If you have an official Bambu Lab reusable spool, you likely don't need to distinguish a generation - but confirm against the checker since this is based on what SpoolNook could verify, not a guarantee no older design exists.
SUNLU
SUNLU's reusable spool has gone through at least three design generations. Only the third generation is documented as accepting a refill coil at all - see SUNLU Gen 2 vs. Gen 3 for the full comparison.
| Generation | Visual clue | Accepts a refill? |
|---|---|---|
| Gen 1 | Closed, solid side walls with minimal cutouts; noticeably heavier in hand | No (not designed for it) |
| Gen 2 | Open, cutout side-wall pattern to save weight; sides are more prone to cracking | No (not designed for it) |
| Gen 3 (2025-) | Detachable multi-hole/porous side walls with a printed weight-scale marking | Yes |
Sourced from an independent SUNLU spool comparison guide and SUNLU's own wiki/store pages - see the Gen 2 vs. Gen 3 guide and How We Verify for full citations.
Prusament
Prusament's spool line has one major, clearly documented split:
- Cardboard-core spool (pre-2025): black plastic side plates clipped onto a cardboard tube. The sides pull apart by hand (or after light soaking) to swap in a refill.
- OpenPrintTag / NFC spool (2025-): carries a large circular NFC tag, readable through the assembled spool in any orientation, and is officially described as 3 mm slimmer than the previous design.
Prusa's own documentation states old cardboard-core refills do not fit the new NFC spool. See Prusament refill compatibility across spool generations for details, including the one direction that does technically work (but isn't recommended).
Separately, Prusament also sells grey "advanced material" spools whose sides are glued to the cardboard core rather than clipped - these are not refillable regardless of generation.
eSUN
eSUN's current reusable spool is the eSPOOL+, a transparent polycarbonate spool. SpoolNook was not able to confirm during this review whether it is dimensionally identical to eSUN's earlier "eSpool" model, and has recorded that as a research gap rather than assuming they match.
Polymaker
Polymaker does not currently sell its own branded reusable spool; its PANCHROMA refills are documented by Polymaker as designed to mount onto other brands' reusable spool systems instead (see the Polymaker compatibility article).
If you still can't tell
When visual identification isn't conclusive, measure your spool's hub (inner) diameter and width directly - see how to measure a refill core for the same method applied to the spool side. Then use the checker with your best-match selection; if nothing matches exactly, it will tell you honestly rather than guessing.
