Where does this downpipe bracket bolt to?

[240meowth]

Hello, new here, doing a engine swap and need a down pipe I'm thinking about getting this one from ebay:

http://www.ebay.com/itm/For-Nissan-2...xXkUXn&vxp=mtr

I notice there are some bracket that reaches out... where the heck does this bolt to?

Is there supposed be some kind of bracket that comes out from the tranny mount that the cat/downpipe is supposed to bolt to? I'm just wondering because it my exhaust keeps falling apart (last one broke off at the cat) maybe the exhaust system isn't supposed to just be hanged by the exhaust hangers...