A quarter stick is a large firecracker that falls within a certain range of dimensions. Typically, a quarter stick consists of a thick walled cardboard tube containing approximately 1 oz. (28.4 grams) of pyrotechnic flash powder, with a short length of Visco fuse protruding from the side or end of the device. No true standard for dimensions and construction exists, as these devices are products of bootleg manufacturers.
The term quarter stick is based on a quarter-stick of dynamite, which it somewhat resembles. However, quarter stick firecrackers do not contain nitroglycerin as dynamite does, and have far less explosive power.
In the United States, quarter sticks and similar large firecrackers are illegal to manufacture or possess without a BATFE High Explosives Manufacturing License.
They are sometimes colloquially known as M-1000s or "block busters".