Sackbut, (from Old French saqueboute: “pull-push”), early trombone, invented in the 15th century, probably in Burgundy. It has thicker walls than the modern trombone, imparting a softer tone, and its bell is narrower.

sackbut Sackbuts. Multimann

Britannica Quiz A Study of Composers Which of these was a famed English madrigal composer?

The sackbut answered the need for a lower-pitched trumpet that composers of the time sought. Its telescoping slide mechanism is retained in the modern trombone.