is a proximity fuze. It is a nose electronic fuze that does not require impact to trigger. Designed to detonate close to the target. It was originally intended to be used against air targets. Now it is also used in shore bombardment and surface actions against fast boats. This is because the VT fuze has proved well suited for bursting the shell at the correct distance above the ground or water for maximum damage to lightly armored targets over a large area. Auxiliary detonating fuze In the projectile drawing, an Auxiliary Detonating Fuze is screwed onto the bottom of the Mechanical Time Fuze. This is because the time fuze primer does not have enough explosive shock to detonate the relatively insensitive Explosive "D". The Auxiliary fuze uses an intermediate explosive that is set off by the time fuze primer, and in turn, sets off the Explosive "D". Powder case The powder case is a brass or steel alloy cylinder closed at one end. It holds the propelling charge and a case combination primer. The charge is held packed around the primer by a wad, distance piece (not in clearing charge), and plug. When rammed in the chamber with the projectile, the Full and Reduced charge cases are designed to completely fill the volume of the chamber from the breechblock face to the base of the projectile when its rotating band is jammed into the bore's rifling. In other words, the powder case acts a rammer extension for the projectile. There are three types of powder cases: Full service charge (pictured) A 26.7 inch (679 mm) long, 12.3 pound (5.6 kg) brass case with 15.5 pounds (7.0 kg) of smokeless or flashless (used at night) powder. The Full Service Charge new gun initial velocity is . It is used in surface and anti-aircraft actions. Reduced charge The Reduced Charge uses the same case as the Full Service Charge, but with only of powder and a longer distance piece. The Reduced Charge new gun initial velocity is . It is used in shore bombardment to lob shells, like a mortar, over obstacles to hit targets on the opposite side, and for propelling star shells at a lower velocity to protect the parachute from being shredded while it is deployed. Clearing charge (Pictured) The clearing charge (also called, "the short round") is a short case; plugged just above the wad. The distance piece