What the code means

IMS product codes describe the basket. In B702TFH24, B70 is the 70 mm rim diameter, 2T is two cups (a double), FH is a flat bottom, and 24 is the height in millimetres. Every basket in this range shares the same 49 mm perforated area and the same 715-hole hexagonal pattern, so the only thing that changes between them is how much coffee they hold and how far the puck sits below the shower screen.

Choosing a height

Capacity is a volume limit, not a weight limit. Darker roasts are less dense and take up more room, so you will sit toward the lower end of the stated range with a dark roast and the upper end with a light one. A basket taller than your dose needs leaves a large headspace above the puck, which is worth avoiding on machines with a shallow group.

Ridgeless, flat bottomed, rounded at the corner

Ridgeless means the walls are smooth all the way down, with no internal groove for the portafilter’s retaining spring. That gives a cleaner tamp with nothing for coffee oils to collect in, but the basket is not locked in place, so it can drop out when you knock the puck against a knock box. In a bottomless portafilter this is not an issue.

The perforated floor is flat, but the junction between wall and floor is deliberately radiused rather than square. IMS calls this a specific corner rounding at the base, shaped so the whole puck stays in play and the spent puck releases cleanly. It is the most visible difference against a VST basket, which meets its floor at a much sharper corner. A flat floor tends to give a clear, well-defined cup that leans toward acidity, where the convex-bottomed baskets in the same family funnel flow toward the centre and build more body.

Tamper size and grind

The walls are straight and precisely sized, so a 58.0 mm tamper leaves a ring of uncompressed coffee at the edge and invites side channelling. IMS recommends 58.4 mm or wider, which makes something like the Normcore V5 spring loaded tamper with its 58.5 mm base the right pairing. A flat tamper seats on the flat floor and cannot reach into the rounded corner, so the outermost few millimetres of coffee always end up slightly less compressed. Getting the grounds evenly distributed before you tamp matters more than trying to solve this at the tamper, and a quick pass with a Subminimal Flick WDT tool does most of that work. Expect to grind finer than you did with your stock basket, since the larger open area and low-friction conical holes let water through faster at the same setting.

Specifications

Machine compatibility

Fits portafilters that take a 70 mm rim basket, including E61 group machines: Astoria, Bezzera, BFC, Bianchi, Brasilia, Conti, ECM, Elektra, Expobar, Faema, Fiorenzato, Fracino, Grimac, Iberital, Kees van der Westen, La Marzocco, La Nuova Era, La Scala, Magister, Nuova Simonelli, Promac, Rancilio, Rocket, SAB, Sanremo, Slayer, Superkop, Synesso, VFA, Vibiemme, Victoria Arduino and Wega.

What’s in the box

• One E&B Lab filter basket in the selected height, in an IMS box

Video

IMS’s own short on the B702TCH24E, the convex-bottom sibling in the same B70 2T family. Construction, perforation and finish are identical; only the bottom profile differs.