Ecoblast Air Fog Horn and PumpBesides being louder than most of its competitors, EcoBlast is powered entirely by compressed air, meaning that it never needs refills and is 100% environmentally friendly. The cylinder can be recharged either by using the mini hand pump supplied, or a tyre inflation compressor. 8" tall, horn length 6". Rechargeable signal air horn Environment friendly chemical free Simply pump in air Works in all weather and temperature extremes Recharges in seconds