Taking from the lessons learned from the StuG III and IV used in a tank destroying role, the Jagdpanzer was the first true AFV designed as a tank destroyer. Improvements included a well slopped superstructure that was 60mm thick in the front. The angle and thickness offered excellent shot deflection.
Also, compare the superstructure between the Jagdpanzer and the StuG III and IV, the Jagdpanzer's superstructure went as far as the track width to allow for extra ammo stowage while the StuG's superstructure ended over the tracks and was completely vertical.

Gun movement ranged -8º to + 10º elevation and traversed 120º left and 10º right. The gun was vary versatile, firing a wide range of rounds. This included, APBE (Armour Piercing Ballistic Cap) at a muzzle velocity of 2300 fps or an HE (High Explosive) round at 1800 fps. Also, a hollow charge, AP40) shot and smoke could be fired.

The Jagdpanzer possessed an ability to withstand some shots. A late war account by an American Lieutenant claims his platoon of 5 Shermans fired 27 AP rounds at a Jagdpanzer IV and failed to penetrate its frontal armour.