What tip would I use to make the end of a paintbrush out of buttercream?

Thanks :)

To make the bristles? Maybe a grass tip
 

AYou almost have to have it laying down to make it and than use tip 1 or 2 and some firm icing squeeze some icing out do enough little strings to make it thick enough for the paint brush that you want it to look like. Dont worry about the ends of the brush until you are done piping , than come back with some small little scissors and trim up the little strings of icing that you just pipped. Remember to use a firm icing so that you can come back and trim the bristles up. Hope this makes sense