Tektronix TDS520D,Aux1 and Aux2 are just for trigger?

Hi to all the people here.

I have the chance of buying a reconditioned TDS520D.

Are the Aux1 and Aux2 channels for trigger purposes only ? Yes,it is clearly declared as a 2 channel oscilloscope(except in some websites),but you could admit that it has a 4 channels look,at first glance.

Thanks Diego