It has 2 tabs that fold below the seat: these get locked in place using the 2 screws holding the passenger strap in place.
It was a VERY tight fit to get the cowl on the seat (had to remove the seat side "locking brackets" as well to get it on). BTW, my bike is Scg, but the seat is from an XB9sx, so that may be the reason. The cowl is supposed to fit the 9 & 12 though I think.