# IMS B70 Competition 1 Cup H18.5 (B701TH18.5N)

> Espresso compatibility data from EspressoFit. Confidence: **manufacturer (Tier 1 — manufacturer primary source read firsthand)**.
> Sources last read firsthand: 2026-08-21.
> Canonical page: https://espressofit.com/baskets/ims-b70-competition-1-cup-h18-5/

## Specifications

- **Diameter:** 58 mm
- **Depth:** 18.5 mm
- **Type:** non-pressurized (single-wall)
- **Brand:** IMS

## Fits these machines

- Breville Oracle (58mm portafilter) — https://espressofit.com/machines/breville-oracle/
- ECM Estetika (58mm portafilter) — https://espressofit.com/machines/ecm-estetika/
- ECM Mechanika MAX II (58mm portafilter) — https://espressofit.com/machines/ecm-mechanika-max-ii/
- Flair 58 (58mm portafilter) — https://espressofit.com/machines/flair-58/
- La Marzocco GS3 (58mm portafilter) — https://espressofit.com/machines/la-marzocco-gs3/
- La Marzocco Linea Micra (58mm portafilter) — https://espressofit.com/machines/la-marzocco-linea-micra/
- La Marzocco Linea Mini (58mm portafilter) — https://espressofit.com/machines/la-marzocco-linea-mini/
- Lelit Bianca (PL162T) (58mm portafilter) — https://espressofit.com/machines/lelit-bianca/
- Lelit Elizabeth (PL92T) (58mm portafilter) — https://espressofit.com/machines/lelit-elizabeth/
- Lelit Kate (PL82T) (58mm portafilter) — https://espressofit.com/machines/lelit-kate/
- Lelit MaraX (PL62X) (58mm portafilter) — https://espressofit.com/machines/lelit-marax/
- Lelit Victoria (PL91T) (58mm portafilter) — https://espressofit.com/machines/lelit-victoria/
- Rancilio Silvia (58mm portafilter) — https://espressofit.com/machines/rancilio-silvia/
- Rancilio Silvia Pro (58mm portafilter) — https://espressofit.com/machines/rancilio-silvia-pro/
- Rancilio Silvia Pro X (58mm portafilter) — https://espressofit.com/machines/rancilio-silvia-pro-x/
- Rocket Espresso Appartamento (58mm portafilter) — https://espressofit.com/machines/rocket-appartamento/
- Rocket Espresso Epica (58mm portafilter) — https://espressofit.com/machines/rocket-epica/
- Rocket Espresso Giotto Fast (58mm portafilter) — https://espressofit.com/machines/rocket-giotto/
- Rocket Espresso Mozzafiato Fast (58mm portafilter) — https://espressofit.com/machines/rocket-mozzafiato/
- Rocket Espresso Porta Via (58mm portafilter) — https://espressofit.com/machines/rocket-porta-via/
- Rocket Espresso R Nine One (58mm portafilter) — https://espressofit.com/machines/rocket-r-nine-one/

## Notes

The **shallowest** basket in IMS's B70 line at 18.5mm — a genuine single-shot
basket rated 6–8 g for a dark roast and 8–10 g for a light one. There is nothing
smaller in the series.

## Truncated cone, and ridgeless

This is not simply a shorter version of the taller B70 singles. IMS gives its
shape as a **truncated cone** and its ridge as **Ridgeless**, and explains the
reason in its own words: the taper 'exploits the whole coffee puck even with
lower quantities, facilitating drying and expulsion'. A thin dose in a
straight-walled basket spreads out into a shallow, fragile puck; narrowing the
floor keeps the bed deep enough to hold resistance.

Ridgeless means the retaining spring has no lip to grip. That is a good match for
a **bottomless** portafilter and worth knowing about if you use a spouted one —
IMS's ridged [M-pattern doubles](/baskets/ims-b70-competition-2-cup-h22-5-m/)
are the line with an external Ø60.5mm ridge.

## The two truncated-cone singles

| Code | Height | Dark | Medium | Light |
|---|---|---|---|---|
| [B701TH18.5N](/baskets/ims-b70-competition-1-cup-h18-5/) | 18.5mm | 6/8 g | 7/9 g | 8/10 g |
| [B701TH19.5N](/baskets/ims-b70-competition-1-cup-h19-5/) | 19.5mm | 7/9 g | 8/10 g | 9/11 g |

Both share the same perforation — 177 holes of 0.30mm in the Normal pattern over
a Ø30mm face, each hole circular with a conical cross-section so flow accelerates
on the way out. One millimetre of height is worth about a gram of dose.

If you want more than 10 g in a single basket, the taller
[H24.5](/baskets/ims-b70-competition-1-cup-h24-5/) and
[H26.5](/baskets/ims-b70-competition-1-cup/) singles use a different approach —
a specific curvature radius rather than a cone — to build a taller puck.

Standard B70 fitment otherwise: La Marzocco, Rancilio, Lelit, Rocket, ECM and the
Breville Oracle. Gaggia is B68, not B70.

## Sources

- https://www.imsfiltri.com/filters/B701TH18.5N.html
  - Official IMS Filtri product page ('B701TH18.5N FILTER BASKET' — 'IMS - Competition B70', '1 Cup - H18.5 Competition'), read firsthand 2026-08-21. Specs verbatim: 'Border: Ø 70 mm', 'Body: Ø 60 mm for Ø 58 mm Tamper', 'Height: 18.5 mm', 'Tamper: Ø 58/58.4 mm', 'Ridge: Ridgeless', 'Shape: Truncated Cone'; perforation features 'Perforated Area: Ø 30 mm optimized for the shape', 'Number of Holes: 177 (Normal pattern)', 'Hole Diameter: 0.30 mm', 'Cross Section: Circular with Conical cross section'. Described as 'Designed with a unique truncated cone shape to ensure the ideal ratio between base and height of the coffee puck. This design exploits the whole coffee puck even with lower quantities, facilitating drying and expulsion.' The page's 'Suggested Quantities' table gives this height as 6/8 gr (dark roasted), 7/9 gr (medium) and 8/10 gr (light), and lists the truncated-cone 1-cup family as exactly two codes: B701TH18.5N and B701TH19.5N.
- https://www.imsfiltri.com/IMS-competition-Catalogue.pdf
  - Official IMS Competition Series catalogue, read firsthand 2026-07-04, whose 'For tamper 58 / 58.4' B70 compatibility list names La Marzocco, Rancilio, Lelit, Rocket, ECM and 'BREVILLE (The Oracle)' among the fitting brands — and 'FLAIR ESPRESSO (58)', which is why the Flair 58 is cross-referenced here; Gaggia is assigned to the narrower B68 series, so B70 baskets do not cross-reference Gaggia machines.

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Compatibility reference, not a substitute for your machine's manual. Every claim above cites the source it came from; see https://espressofit.com/methodology/ for how entries are verified. Corrections: corrections@espressofit.com.