They are produced in a great variety of shapes, sizes, and weights. Small extruded, cast, or pressed boosters are slipped over a detonator to initiate ANFO in small underground boreholes. Boosters typically weigh from 0.11 to 5 pounds, but the most commonly used weighs 1 pound. TNT, composition B. and other such materials used in boosters are imported. There is no commercial U.S. TNT production.
Homemade boosters are easy to produce.
The main charge is the primary source of explosive energy.