It attaches to the rear slider track (rail) and gets pulled up/under/inside of the rear skirt fairing when the canopy is closed. Keeps (some) of the cold air out.
I always give myself a little more room there......somewhere between 5/16" & 3/8". This gives you a nice 'flat' area between the dimple for the pops and forward edge of the skirt......looks a little nicer IMO. You'll also want to tape off the forward edge of the skirts and canopy for a thin bead of the proseal. this will prevent water from running down the plexi and into your baggage area. The paint over the pop rivets has a tendancy to crack along the upper area of the rear skirts. When using the metal skirts you've got a couple choices here.
1-Don't let your buds close your canopy. Folks that are unfamiliar with the operation like to grab the canopy by the rear skirts and LIFT them up as they close it.....this puts a lot of leverage along the upper row of pops and WILL crack the paint over the rivets.
2-Glass over the pops prior to paint. If/when the pops 'move' they'll be under the glass/paint and the paint will hold up a lot longer.
3-Eliminate the pops......dimple for #6 screws and tap the rear bow.