Classed as a guitar and bass tuner (as opposed to the original SN-2's description as an 'all instrument' tuner) the SN-1 is effectively the same machine but with a more limited frequency range.
Not that that should bother guitar and bass players. The only other difference is that there's no mic mode (really only necessary if it won't fit on your headstock), just vibration mode.
And thanks to the well-designed rubber grip clip, it fits on all the guitars and basses, acoustic and electric, we had to hand. The tuner head, which rotates 360 degrees, houses the circular LCD display and unlike some headstock tuners, can be positioned exactly where you need it.
Other features include pitch calibration from 415-466Hz, a tap tempo visual metronome, and a transpose function that keeps the readout E-E even when you're using a capo on the first four frets.
With the same 'engine' as the SN-2, the SN-1 is just as good. There's a clear read-out with fast pitch identification on a variety of guitars, basses and even our ukulele. Superb.