E61 & La Marzocco Bottomless Portafilter and Basket Fit Guide.
"58mm" is not one fitment — it's a basket diameter that several different portafilter ear shapes share. This trips up almost every first-time buyer: a 58mm bottomless portafilter made for an E61 group (ECM, Rocket, Lelit, Profitec, Flair 58) will not seat on a La Marzocco, even though both machines use 58mm baskets. The baskets themselves are interchangeable; the portafilter body and ears are not. Here's how to buy the right one the first time.
Bottomless portafilters: E61 vs. La Marzocco
Both of these are sold as two separate variants of the same product specifically because the ear spacing differs between E61-pattern groups and La Marzocco groups — check which variant you're adding to cart.
- MHW-3BOMBER Walnut Bottomless Portafilter, E61 / La Marzocco — from $94.90. A 58mm naked portafilter with a turned walnut handle. Sold in two fitment variants: "Fits La Marzocco" and "Fits E61 / ECM / Rocket / Flair 58 / Lelit / Profitec, etc." — pick the one that matches your group head.
- Feepie Naked Portafilter, Rosewood Handle 58mm — from $75.90. Same idea with a rosewood handle, available in E61, La Marzocco, and Casabrew fitments, with the option to upgrade to the GOW precision basket at checkout.
Filter baskets: universal across E61 and La Marzocco
Unlike the portafilter body, the basket itself just needs to be 58mm (IMS calls their standard depth/diameter spec "B70") — it drops into either group's portafilter the same way. The difference between baskets is what they do to the shot, not what they fit.
| Basket | Best for | Price |
|---|---|---|
| IMS Precision Filter Basket | 18-20g doses. The "which basket should I own" default: laser-cut, straight walls, evenly spaced holes. | $35 |
| IMS Nanotech Filter Basket | Same precision geometry with a non-stick coating — pucks knock out clean, oils rinse instead of baking on. | $35 |
| IMS Superfine Filter Basket | 20-22g doses at a finer grind than a standard precision basket allows, for more extraction without channeling. | $35 |
| VST Precision Filter Basket, Ridged | The basket that started the modern precision-filter category — ridged wall, competition-grade consistency. | $35 |
Shower screen and puck screen
Two small parts, both made by IMS in Pavia, Italy, that change what hits the puck before and after the basket.
- IMS Nanotech Shower Screen, E61 — $36. Direct swap for the stock E61 shower screen: a stiffer, reinforced plate with a more even dispersion pattern and the same non-stick coating, so it rinses clean instead of baking on. Fits any standard E61 group head. Swaps in with a screwdriver.
- IMS Puck Screen — $29. Sits on top of the tamped puck (not inside the group) to spread the first rush of water evenly and keep channeling down. Sized at 58.5mm for 58mm precision baskets — works on E61 and La Marzocco alike, since it rests on the puck, not the group.
Once your portafilter fitment is sorted, see our WDT tool buying guide for the distribution step that happens before the basket goes in, or browse the full prep tools collection.