I have played with the one time use canned air horns, and while they are lots of
pranking fun, they don't tend to last long before you have to throw them in the trash. The Taylor Made EcoBlast Air Horn is refillable. After you have honked the last honk, simply attach the included air pump or an air compressor to refill. Honk on!
Perfect for sporting events or boating trips. Did I mention it is very loud, 120db loud. Yours for under $40 here.