There are 2 knobs just in front of the bridge saddles. When you turn them clockwise they move a piece of foam rubber upward until it touches the strings, muting them. You can adjust the tension for a little mute to a lot.

It is really cool, with just a bit of muting it just reduces the sustain, with a lot it sounds really toneless, like just a thump. It's hard to describe, you'll just have to try it.

I think Rics might be the only bass with a built in mute.

Thats an interesting option. It seems like rics are made to have huge sustain. I guess I'll have to try it out.

Here's some pics.

Tailpiece, see the two knobs near the front.



Mute bar.