EspressoFit

IMS basket codes, decoded

IMS product codes look like line noise — B702TH24.5M, B682TCH26.5E, B702TFH24NT — but every character is doing a job, and once you can read one you can tell at a glance whether a basket will fit your machine and what dose it's built for. This is the code structure in IMS's own terms, then every code in our database with a link to its verified spec.

Reading a code, character by character

Take B702TCH26E:

B70 — the series, and the part that decides fitment
IMS describes this as "Border and portafilter compatibility". The number is the border diameter in millimetres — the outer lip that has to seat in your portafilter. This is the only part of the code that determines whether a basket physically fits, which is why a B70 and a B68 are not interchangeable even though both are sold for "58mm" machines.
2T — the dose
"Dose convention for one or more cups": 1T is a single, 2T a double/triple. See also single- vs dual-wall baskets — all of these are single-wall (non-pressurized).
C or F — the bottom shape
C marks "cylindrical filters with a convex bottom"; F is a flat bottom. A convex floor concentrates flow toward the centre of the puck. Where neither letter appears, the basket is the standard profile for its series.
H26 — the height, and therefore the dose range
"Filter height and capacity range", in millimetres. This is the number that matters most day to day: a deeper basket holds more coffee, so an H26.5 suits an 18–20g dark-roast dose while an H19.5 is a 7–9g single. Match the height to the dose you actually pull.
E, N, M — the hole pattern
The "hole-boring pattern" (IMS lists N, E, M, BB and All-in-One). The pattern sets how many holes sit in how wide an area — an M-pattern B70 packs 641 holes, while a 1-cup E-pattern concentrates 253 holes into a Ø30mm area to keep resistance up under a small dose. Holes themselves are 0.30mm, "circular" with a "conical cross section".
NT / SF — optional suffixes
NT is IMS's "Nanotech coating" for a non-stick surface and easier cleaning; SF is a "Superfine filter" at roughly 170µm.

The series decide fitment — sizes don't

The single most useful thing the code tells you is the series, because IMS assigns series to brands, not to nominal portafilter sizes. A Gaggia and a Rancilio are both "58mm" machines, yet IMS puts Gaggia in B68 and Rancilio in B70. Buy by series, not by the number on your portafilter.

Every IMS code in this database (34)

Each links to its entry, where the full spec is quoted from IMS's own product page with the date it was read.

B70 series (18)

B68 series (3)

B64 series (2)

B62.5 series (9)

B60 series (2)

How we verify

The code structure above is quoted from IMS's own filter code guide; every basket's dimensions come from its IMS product page, read firsthand and dated on the entry. See how we verify compatibility, or use the parts finder to jump straight to the baskets confirmed to fit your machine.