IMS Shower Screen And Filter Baskets

If your espresso channels, tastes uneven, or never quite repeats, the basket and shower screen are where the fix usually starts. IMS makes Precision-punched filter baskets and integrated-membrane shower screens for 58mm groups, E61 groups and 54mm Breville portafilters. We've been fitting IMS parts to home and café machines since 1999, so this page covers the full range, how the hole geometry works, and how to pick the right IMS filter basket for your group.

What the holes actually do

A filter basket's job is to let water leave the puck evenly. IMS perforation is patented, with the perforated area sized in proportion to the basket shape. On the Big Bang pattern that is 497 holes across a 44mm area, with spacing that increases toward the edge. The B68 2TH ridgeless basket carries a 641-hole pattern. A more uniform open area gives more even flow resistance through the puck, which is what reduces channelling. Stephen Mackenzie makes the same point in Engineering Better Espresso: the change from grounds to espresso happens inside the basket, so basket quality shapes the result.

Integrated-membrane and Precision shower screen options

IMS competition screens carry a membrane created inside the shower body and fixed by caulking, so there is no separate disc to lose or clog. The MA 200 IM and RA 200 IM use 98 holes of 3mm with 200 micron filtering. The E61 and Rancilio wire-membrane screens filter finer, at 35 micron. The NanoQuartz coated MA200NT adds a non-stick surface that resists limescale and coffee residue.

Fit before upgrade

The most common mistake we see is ordering on dose alone. A B70 2T basket for a 58mm La Marzocco group is a different part from a B62.5 Big Bang built for a 54mm Breville portafilter. Check the group first, dose second.

Step one: match the group, not the dose

Every IMS basket is built to a group standard. The B70 family (70mm border) fits 58mm groups across Astoria CMA, Bezzera, ECM, Expobar, Faema, La Marzocco, Nuova Simonelli, La Pavoni, Rancilio, Sanremo, Slayer, Synesso and Vibiemme. The B62.5 Big Bang family is the IMS Breville basket range, built for 54mm Breville and Breville portafilters. The B68 family sits at 68mm and suits Carimali, Cimbali, Gaggia and Reneka groups. Order the family your group takes before you look at anything else.

Step two: pick your dose band

For a single, the B70 1T H26.5E covers 7 to 9g. For a double, the B70 2T H24.5M covers 12 to 18g and the B70 2T H26.5M covers 16 to 20g. The ridgeless B70 2T CH28.5E is the competition double at 18 to 22g. On 54mm machines the Big Bang comes in four heights: 21.5mm for 14/16g, 23.5mm for 16/18g, 25.5mm for 18/20g and 27.5mm for 20/22g. Ridgeless baskets seat slightly differently and pair well with a bottomless portafilter for diagnosing channelling.

Step three: the shower screen above it

An IMS espresso basket works best under an even shower. If your screen is pitted, scaled or clogged, replace it. IMS screens are group-specific: the MA 200 IM fits La Marzocco, Synesso and Slayer; the RA 200 IM suits Rancilio; the E61 200 IM and E61 NanoQuartz screens fit E61 groups; the 48mm SM 200 IM covers San Marco Beverage Systems and Dalla Corte. The MA200NT with NanoQuartz coating is the pick in hard-water areas.

IMS or Vst?

Both are Precision baskets and we stock Vst alongside IMS in our Precision baskets range. The honest answer is that fit matters more than the badge: choose the family that matches your group, then the dose band you actually use, and either brand will show up a distribution problem a worn stock basket was hiding.

What to pair it with

A new basket exposes distribution errors, so a WDT tool and a puck screen earn their keep here. For replacement screens by machine rather than by brand, our shower screens spare-parts category lists parts by group. We've tested this gear behind the counter and stock the cleaning chemicals that keep membranes clear between backflushes.

A Precision basket is one piece of the extraction chain. To get the full benefit, pair your IMS basket with a bottomless portafilter so you can see channelling as it happens, a WDT tool to break up clumps before tamping, and a fresh shower screen so water arrives evenly. A puck screen on top keeps the IMS membrane cleaner between backflushes. Dialled in, that combination is where consistent, repeatable shots come from, not from any single part on its own.

I'll be straight with you: a basket swap is the least expensive meaningful upgrade in espresso. My dad started this business in 1999 because he couldn't find a part for his Faema E61, and the IMS E61 screens still sit in the same drawer that whole story began in. Once you've pulled a shot through a properly punched basket you feel the difference. We've been selling these to home setups and busy cafés for a long time, and the advice is the same for both: get the group right, then let the holes do their work.

— Pedro Lara

Frequently Asked Questions