A later variant, napalm-B, also called "super napalm", is a mixture of low-octane gasoline with benzene and polystyrene. It was used in the Vietnam War. Unlike conventional napalm, which burns for only 15–30 seconds, napalm B burns for up to 10 minutes with fewer fireballs. It also sticks better to surfaces, and offers improved destruction effects. It is not as easy to ignite. This reduces the number of accidents caused by soldiers smoking. When it burns, it develops a characteristic smell.