Achieve a lower retention on every grind* for an easier single dosing experience and cleaner grinder with this bellows upgrade. This 3D printed flexible part fits in between your Fellow Opus hopper and stock lid and transforms it into a blower.
[Design Features]
Simplicity and maximum effectiveness are my design goals, and both are carefu...
Reviews
4.9
14 ratings
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A huge upgrade
I've had constant retention issues from the start and not unusual to see 6-7g retention at a grind setting of 5. Fellow seem to think this is acceptable, I don't!
This bellow solves this issue to a large degree. I'm not getting results that I consider more than acceptable ( 0.2g or so) I initially picked up a cheaper silicone and is was terrible.
This by contrast is a perfect fit and looks like it was always meant to be part of the grinder. Kudos for the 3d printing design and work as it's not an easy thing to design and get right.
I'm super impressed and if anyone is on the fence about getting one then I'd urge you to look no further.
This is the one.
D
Daniel · July 19, 2025
Works well. Bit more air would be nice also.
C
CARLOS · June 22, 2025
Brilliant
It just solves the problem of not getting all the ground coffee out of the grinder. Perfect solution. Thank you!