The Mortier de 150 mm T Modèle 1917 Fabry was the standard French heavy trench mortar of World War I.

The tube was supported by two recoil-recuperators in a flask-rocker assembly that was mounted on a platform with six fixed spades.

The finned mortar "bomb" was loaded from the muzzle, but the propellant was loaded from the breech and ignited by a percussion ignition system.

[1] For transport it was broken down into three loads, each towed on machine gun carts by either one horse or eight men.

Each cart also carried twenty 17-kilogram (37 lb) bombs.