The FZ-3 is the 2nd fuzz in the line of compact Boss pedals (the first one is the FZ-2 Hyper Fuzz).
It has been sold from 1997 to 1999, however it seems to me that finding an used one is not a problem.
Right now Boss is selling the FZ-5, which is completely different and uses COSM technology for classic fuzz emulation. This last model does not emulate the FZ-2 or FZ-3, anyway 
In Boss intentions, this pedal should have a classic ’60 sound, however I’m not sure if this can be considered true, since I don’t have any classic fuzz like the Maestro or Dallas Fuzzface available for comparison.
As you can see in the above photo, the controls are very simple, and this is a deliberate step back from the FZ-2, which had more controls.
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