bose system integration adapter

Has anyone used this adapter? http://www.crutchfield.com/S-1VWgjReal89/cgi-bin/prodview.asp?i=142C4NN03

What does it do?

i haven't used that exact one but i've used one like it. it allows you to use non bose components like speakers, head units, etc. with a bose stereo. if i wanted to take my bose deck out, but keep the speakers in the car, i would wire the new stereo into that, then wire that into the rest of the system