Switzerland's PAK 50 and PAK 57 anti-tank guns are no longer being produced, but they are still in service with the Swiss Army's infantry.
Both the PAK 50 and the PAK 57 anti-tank guns are very useful in built-up areas, as they can hit the more vulnerable parts of a tank from a close range.
The PAK 50 and PAK 57 anti-tank guns are both of 3.54 inch (90mm) caliber.
At 1,391 pounds (631kg), the PAK 50 anti-tank gun is the lighter of these two anti-tank weapons.
It fires a 4.3 pound (1.95kg) HEAT warhead up to a range of 656 yards (600m).
The PAK 57 weighs 1,578lbs (716kg). The maximum range of its 5.96 pound (2.7kg) HEAT warhead is 874 yards (800m).
Both guns have shields fitted to protect the crew.
The PAK 50 anti-tank gun is fitted with a muzzle brake, but the PAK 57 is not.
Both of these anti-tank weapons are said to be are capable of firing up to ten rounds per minute, but it is doubtful that they can sustain this firing rate against moving targets.
The PAK 50 and 57 anti-tank guns are each operated by a five or six man crew. The guns are fired from a platform on a two-wheeled carriage.
The guns are usually towed, but they can be carried easily by the Swiss Army's Super Puma helicopters for rapid battlefield deployment.