The only thing I can say about this product is save your money. It's worthless.
Positive Product Points
This thing looks great Has neat portable design
Negative Product Points
Next to worthless Hard to hold Harder to turn Impossible to get anything close to a consistent grind
The GSI JavaGrind looks like it would be great and even features a hard lexan body, ceramic burrs and a handle that locks in. But functionally the JavaGrind is just a total nightmare. Unlike the main body, the top of the grinder is a very thin plastic that deflects substantially during grinding. This causes the burrs, which are adjusted based on distance from the top, to move up and down, with the effect of constantly changing the size of the grounds. The lexan body, while nice, is unfortunately far to wide for the average person to hold it steady. And to top it off, the handle scrapes the top of your hand if you can manage to grip it.
REI is always great. Only wish I had saved the box so I could return this piece of crap.