Best bottomless portafilter: match the fitting, not the diameter

For a Breville Bambino, Barista Express, Pro or Touch, the LILQ 54 mm. For a Gaggia E24, the KNODOS 58 mm Gaggia part, the only listing in this read that names the E24. For a CASABREWS CM5418 or 3700 Essential, CASABREWS’s own 51 mm. Do not buy one at all if you use pre-ground coffee or the pressurized basket your machine came with. A bottomless portafilter shows you what the shot is doing. It does not fix it, and without a grinder you can adjust, it mostly shows you a mess.

The thing that decides which one to buy is not the diameter. It is the fitting: the diameter, how many ears the head has, and how thick those ears are. Get any one of the three wrong and the part will not lock into your group head.

58 mm is not one size

The listings say this themselves. Normcore, the best-selling bottomless portafilter in this read, sells its 58 mm version in at least five fittings within one listing family: E61 group heads, Breville, Nuova Simonelli, Gaggia and WPM. KOFIKOFI sells three separate 58 mm parts, for Breville, Gaggia and E61, and its Gaggia listing says plainly that other 58 mm machines are not compatible. 51 mm parts come with two ears or three, and De’Longhi parts are sold both ways, depending on the model.

Ear thickness is the detail almost nobody prints. Two listings in this read do. The stochastic box Breville part states three ears 5.5 mm thick. The fogkay CASABREWS part states three ears 4 mm thick and tells you to check your original portafilter before ordering. That is the right advice for any of these. Count the ears on the portafilter you already have, and buy a part whose own listing names your machine.

What it does, and who should skip it

A bottomless portafilter has no spouts and no base, so you watch the coffee leave the basket. An even shot comes out as one steady stream. A shot with channels, where water has found a path through the puck, sprays sideways or comes out of one spot first. Two of these listings warn you about exactly that, and say that spraying is a sign of grind, dose or tamp problems, not a fault in the part.

That is why it suits some owners and not others. It is a diagnostic tool for people who grind their own beans and can change the grind. If you buy pre-ground coffee, you have nothing to adjust when the shot sprays. Pressurized (dual-wall) baskets exist to hide uneven puck preparation, so a bottomless portafilter has little to show you with one. The CASABREWS part ships with a non-pressurized basket, so fitting it changes how the machine brews, not only what you can see. The beginners’ guide explains the steps you would be taking on.

Breville 54 mm: four listings, one clear record

The Bambino, Bambino Plus, Barista Express and Barista Touch listings all state a 54 mm portafilter. The Barista Pro’s own listing names no size, but three of the four 54 mm parts below name the Pro. This is where most of the choice is. Four listings came up repeatedly in Amazon’s results. Here is what each one states.

Two of those rows decide more than they look. The stochastic box part ships with a puck screen and no basket, so it only makes sense if you already own a single-wall 54 mm basket. And only one of the four listings, KNODOS, names the Bambino Plus. If you own a Bambino Plus, that is the only listing here whose own copy claims your machine. The Bambino Plus review covers the machine itself.

Then the review topics, which separate them more than the specs do.

The KNODOS 54 mm has the most to like in its listing, including the longest compatibility list and an 18–21 g basket. Its leakage topic is the problem: 92% negative across 24 mentions, the most one-sided topic on any listing here. Ease of use runs 60% negative too, and Amazon’s summary for it mentions the handle unscrewing. Leakage at the group head is the one failure that makes a portafilter unusable, so it is the topic to weigh first.

Normcore is the hardest to read. It is the best seller by a distance, ranked #8 in Espresso Machine Replacement Parts, and its 2,525 reviews are more than the other seven listings here combined (1,610). But that corpus covers every size and fitting Normcore sells. Its fit topic is only 53% positive across 150 mentions, with stability 25% and leakage 25%, and there is no way to tell how much of that is about the 54 mm Breville part. A fit topic that mixed, pooled across dozens of fittings, is what you would expect from people who bought the wrong one.

For a Breville: the LILQ 54 mm

The LILQ is the only one of the four with no negative topic published. Fit and compatibility both run above 90% positive. Its listing names the Bambino, Barista Express, Pro and Touch, includes an 18–20 g basket, and makes one specific claim the others do not: that the handle is fixed to the head and does not unscrew. That matters, given that Amazon’s summary for the KNODOS mentions handles unscrewing.

What it gives up: evidence. It has 94 reviews, and its topics rest on a few dozen mentions. Its listing does not state an ear count, and it does not name the Bambino Plus in its own copy. If you own an Express, the Barista Express review covers the machine it most often gets paired with.

If you already own a single-wall basket and want a part that states its ear count and thickness, the stochastic box is the alternative. Its fit topic runs 88% positive. Its durability topic is only 44% positive, across 16 mentions.

For a Gaggia E24: the KNODOS 58 mm Gaggia part

The Gaggia E24 is the only machine in this site’s data with a 58 mm portafilter apart from the Oracle Touch. You might expect that to make it the easy case. It does not, because 58 mm is the size with the most fittings. Of the 58 mm Gaggia listings in this read, one names the E24 in its own copy: the KNODOS, which lists the Classic Pro, Evo, E24 and GT. KOFIKOFI’s Gaggia part names the Classic family and says other 58 mm machines are not compatible. Normcore’s Gaggia listing names the Carezza, Cubika Plus and Gran Gaggia models.

Some E24 owners report on other listings that those parts fit. That may well be true, but it is not the seller’s claim, and this page does not assume one Gaggia fitting covers every Gaggia.

The KNODOS evidence is thin. It has 63 reviews, with quality 82% positive across 11 mentions and compatibility across 5, and it ranks well outside the category’s top 100. It is recommended here because it is the only listing that claims the E24, not because its record is strong. The E24 against Bambino comparison explains why the 58 mm group is the E24’s main advantage.

For a CASABREWS: the CASABREWS 51 mm

Both CASABREWS-fit parts here name the CM5418 and the 3700 Essential, both state three ears, and both include a basket and a puck screen. Neither published any review topics on this read, so there is no buyer pattern to separate them. CASABREWS’s own part wins on the one point that matters most for a fitting, which is that the maker of the machine says it fits.

Its listing contradicts itself on dose. The bullets suggest 15–16 g for a double, and the description suggests 14 g. The fogkay listing states its basket holds up to 16 g. Read either as a range to start in, not a measured figure.

When the shot sprays: finer or coarser?

This is the tool for this page, because it covers the question a bottomless portafilter raises: you can now see that the shot went wrong, so which way do you turn the grinder? It gives a direction from your shot time, not a number of grinder steps, because step size differs on every grinder.

Who should not buy one

Pre-ground coffee or a pressurized basket: skip it, for the reasons above. Breville Oracle Touch owners: none of the parts on this page names it. Normcore and KOFIKOFI both sell separate Breville 58 mm variants, so buy only a listing that names the Oracle Touch itself. Ninja Luxe Café owners: no listing in this read named it. Bean-to-cup owners: there is no portafilter to replace. The super-automatic guide covers those machines.

Where this leaves you

Breville Bambino, Barista Express, Pro or Touch: the LILQ 54 mm. Bambino Plus: the KNODOS 54 mm is the only listing that names it, with its leakage topic in mind. Gaggia E24: the KNODOS 58 mm Gaggia. Gaggia Classic family: the KOFIKOFI 58 mm. CASABREWS CM5418 or 3700 Essential: the CASABREWS 51 mm, or the fogkay if you want stated ear thickness.

What this page cannot tell you

We have not used any of these parts. There is no test rig, no kitchen and no sample unit, so nothing here is a claim about how a part fits or performs in practice. The tables are what each listing states, and the review figures are Amazon’s topic counts, read 23 October 2026. Fit claims are the sellers’ claims. Check your original portafilter’s ears against the listing before you order.

Price figures on this page: LILQ 54 mm $46.00; stochastic box 54 mm $29.98; KNODOS 54 mm $49.99; Normcore 54 mm $69.99; KNODOS 58 mm $49.99; KOFIKOFI 58 mm $35.98; CASABREWS 51 mm $36.99; fogkay 51 mm $27.99, all read 23 October 2026. Ratings, review counts, ranks, review topics and listing claims were read from each listing on the same day.