Google said:Volume control knob for each pickup, master tone control knob and active bass-boost control knob
Drunk buying it is DANGEROUS! Last time I was drunk I bought a ESP LTD B1004 Multiscale which I didn't remember buying (with Overnight Shipping), and I was surprised with the next day when I opened my front Door, and there it was a huge box with my name on it.LOL. Drunk buying can bring forth many blessings sometimes. If yours is like my VM Jag bass, it's just two stacked knobs. Dome knobs are for each pickup. The rings are for the corresponding tone roll off for each. Simple as it gets. I think the Duncan Designs even sound good. I'm keeping them in it for now. Whatta bargain.