What is "davidka"

The Davidka (, "Little David") was a homemade Israeli mortar used in Safed and Jerusalem during the early stages of the 1948 Israeli War of Independence. Its bombs were reported to be extremely loud, but very inaccurate and otherwise of little value beyond terrifying opponents; they proved particularly useful in scaring away both Arab soldiers and civilians. It is nominally classified as a 3-inch (76.2 mm) mortar, although the bomb was considerably larger.