(h) - Hammer-on (fretting hand only)
Take this bass line:
D---------------------------
A--4------------4----------
E------6------4-------------
B----------4----------------
Db (1), Bb (6), Eb(2), Ab(5), Db
You can add this fill-in:
D-----------------------------------------
A--4-------------------------------------4
E---------------4--------4--6(h)-----4---
B-----4--6(h)-----6(h)-----------4------
Db, quickly (Eb, F, Ab, F, Ab, Bb), Eb, Ab, Db
NOTE: On one of my basses, a 4 string, I have it setup with strings from a 5 string bass. It's the same difference though. It just makes it easier for me to thumb the strings twice. (like Victor Wooten...need more practice, but I'll get it.)