Gaggia’s own-branded IMS competition filter — a 20g Nanotech basket sold with
Gaggia’s bottomless filter-holder for the Classic. Note the nuance: its 70 mm
figure is the IMS B70 border diameter, the wider 58/58.4 mm-tamper series
— whereas the stock Gaggia Classic portafilter takes the narrower B68
(Ø 68 mm) series. Gaggia’s own bottomless holder (59 mm housing) accommodates
this wider B70 filter, which is why Gaggia pairs them. So this basket fits the
Gaggia Classic via Gaggia’s bottomless filter-holder, not necessarily the
stock two-eared portafilter. Non-pressurized, AISI 304 steel, 661 holes.
Verified against Gaggia’s official accessory page on 2026-07-07.
FAQ
What size portafilter is the Gaggia Barista Pro IMS Filter 20g Nanotech for?
It is a 58mm basket, 26mm deep, for 58mm portafilters.
Is the Gaggia Barista Pro IMS Filter 20g Nanotech pressurized?
No — it is a non-pressurized (single-wall) basket, for freshly ground coffee.
Does the Gaggia Barista Pro IMS Filter 20g Nanotech fit 54mm machines like the Breville Barista Express?
No. It is a 58mm basket, so it does not fit Breville's 54mm machines or any 54mm portafilter.
Which machines does the Gaggia Barista Pro IMS Filter 20g Nanotech fit?
Gaggia Classic GT; Gaggia Classic Pro (E24) — each confirmed against manufacturer sources (listed below).
Sources
https://www.gaggia.com/accessories/bottomless-filter-holder-and-barista-pro-filter/(archived) — Official Gaggia accessory page, read firsthand 2026-07-07. States verbatim: 'Barista Pro IMS Filter 20 gr Nanotech: the filter holes are specifically designed to ensure uniform extraction and the best in cup result, avoiding channeling. Filter diameter: 70 mm. Height 26 mm. 661 holes. Aisi 304 steel.' Sold on the same page as Gaggia's 'Bottomless Filter-holder ... for Gaggia Classic. ... Filter holder diameter: 59 mm.' The 70 mm figure is the IMS B70-family border diameter (the basket seats on a 58 mm portafilter); an IMS-made, non-pressurized competition-style filter.