Did you know that most vintage bras from the 1950s have a French back? What exactly is a French back? The simplest explanation is that a French back is doubled over elastic with either a hook and eye or G hook closure. The Jet Set bullet bra pattern is drafted with the French back in mind. The back band on the Jet Set is drafted from direct measurement minus 25% for ease. You can adjust the length of the wing or the length of your elastic depending on which type of closure you want to use. With the Jet Set, the possibilities are endless.