Foil Balloon Happy Birthday Flowers, These Foil Balloon Happy Birthday Flowers will be shipped flat to you (so NOT filled with helium andor air). This foil balloon is suitable for filling with air and helium. To fill with air you need a straw (not supplied as standard). The foil balloon is made of foil and NOT plastic. Do not fill the balloons with a compressor, this will cause the balloon to burst (no guarantee). You will only receive the balloon. Images of the floating balloon have been added for illustration purposes. Diameter before inflation approx. 45cm, diameter after inflation approx. 35 cm (14).