Kolstein's "Adjustable Harmonic" seasoned ebony tailpiece is top-quality, and offers adjustable intonation control for each individual string's afterlength. Beautifully crafted, with a subtle but classy inlaid "K" on the face, it includes a stranded tailpiece cable (no clamp).
The adjustable feature is simple but effective; the individual saddles for each string slide within their own channels and have over an inch and a half of adjustability. String tension holds the saddle in place when the bass is tuned up.
Now, you might ask, "why would you want to adjust the saddles on the tailpiece - that doesn't affect the playable length of the string?" Good question!
What we've learned is that the short answer is this: Having more control over the "afterlength" (the non-playable range of the string between the saddle of the tailpiece and the bridge) can actually have a notable impact on tonal quality; its own vibration, audible or not, can work for or against the overall sound of the string and the total instrument. (As an example, some luthiers tune the afterlengths to 2 octaves and a fourth above each string's pitch.) With a traditional fixed saddle, most luthiers can only "get close" across the 4 strings - with this tailpiece, you can adjust each string's afterlength individually.
What's particularly attractive about it is that it has its useful adjustability - and yet still maintains a traditional look.