Pink GIRL Foil Balloon and Blue BOY Foil Balloon Pink GIRL Foil Balloon and Blue BOY Foil Balloon. Material: Foil. Can be floating when it is blow up with helium. Easy to inflate with a straw or an air handheld pump. Reusable: Self-sealing valve for inflating and deflating. Please note balloons are sent flat packed and NOT pre blown up!