The Korg GA-1 solo tuner is the standard Korg 'black box' tuner that is available in several models. It's black plastic housing slightly larger than a credit card. Runs on two AAA batteries. 1/4' Input jack; Guitar/Bass pushbutton; Flat button for tuning down; Sound button for audible notes; digital needle readout; LEDS for flat (red)/ in tune green) / sharp (red). Easily fits in a shirt pocket, on a music stand or in a gig bag. I've been playing bass professionally for 45 years.
Purchased at a local music store for $19.95 + tax. Needed a tuner that could handle a low B on my bass. the stompbox tuner I inherited wouldn't do so.
The Korg GA-1 is easy to use -- plug in, select guitar or bass, play the note and tune. Although I don't run flat tuning, the switch for Flat would come in handy for 4-string bass players who tune down or for guitarist who tune down for metal.
It would be nice to have a backlit needle display, but the LED readout makes tuning easy even in dark environments.
I'm familiar with Korg tuners and metronome and they will survive a fall from a music stand or amp with ease. I wouldn't put a lot of weight on the plastic case, but it will survive normal use.
The Korg GA-1 'Solo' tuner for guitar or base is a great value for less than $20. It tunes six-string basses or even 7-string guitars, offers Flat tuning and audible note for each string through a built-in speaker. Easy to use. It's not a stompbox tuner, but it's handy for practice rooms, backstage or for setting the harmonics in a workshop environment.