The new HMO1234ze used in Sonic Blast Horns is a specially formulated non-flammable propellant that has an ultra-low global warming potential (GWP). It has a 99.5% lower GWP than HFC-134a and is ideal for uses where flammability is a concern, including boating, manufacturing plants, construction sites, etc.It is not considered HAZMAT, and needs no special documentation. This 5 oz Sonic Blast horn provides up to 56 blasts per can.a High impact white plastic trumpeta Meets USCG requirements for boats to 65 ft (20 m)a Provides a 120 dB sound level at 10 ft