This windchime is cut from a wine bottle and measures 18" to 25" long by 3 to 4" wide.  We chose an American Flag cut in the shape of a star for the design.  It is hung with heavy test fishing line so it can last a long time in or outside.  
I tend to leave mine out most of the year.  The rule of thumb I follow is if the patio umbrella or outside anything have to taken down due to poor weather, so should the wind chime. 
I left mine out during a snow storm one year.  I think it would have alright until the flag blew off and hit it to the ground. Bummer.