Floor tom

A floor tom or low tom is a double-headed tom-tom drum which usually stands on the floor on three legs. However, they can also be attached to a cymbal stand with a drum clamp, or supported by a rim mount. It is a cylindrical drum without snare wires, and tend to produce a booming, resonant sound which can vary in pitch.
The floor toms are the lowest tuned drums played with sticks on a regular drum set. Common sizes are
Floor toms can be mounted:
The floor tom was popularized by Gene Krupa in the 1950s, using a 16x16. 
The floor tom is also used as a small bass drum by some (mostly jazz) drummers. In that case it is mounted horizontally on a specially designed rack system. More recently, companies such as Pearl have come out with "floor tom to bass drum conversion sets". These commonly consist of strategically shaped rods that one can put in place of the floor tom legs to stand it up horizontally. Under this method, it is fairly common that a drummer get appropriately sized bass drum hoops to complete the conversion process.
Floor toms are also used in music parades, often being carried and then lifted up and hit to add effect. It can also be used as a substitute for surdo in samba and bossa eir.