M10

The M10 tank destroyer, also called the Wolverine by the Tea Drinkers, was an allied Tank Destroyer in service with from 1943 to the end of the war.

IRL

The M10 was developed in anticipation of fighting the German Blitzkrieg tactics, using the American Tank Destroyer doctrine of light armor, but a big fuckoff gun. To accomplish this, a 3" gun was strapped into an open turret on top of a modified Sherman hull for the prototype. The hull was given sloped armor along with a pentagonal turret to add some extra defensive capabilities to the vehicle. The final 300 vehicles were given 76mm guns to give them better performance over the 3" M7. For additional anti-aircraft and anti-personnel defence, an M21918 MG was strapped to the top.

The Wolverine performed adequately, but was found to not conform to the American Tank Destroyer doctrine of WWII due to it's heavier hull. The Army in the Pacific hated the vehicle due to the open top making them vulnerable to Japanese zerg tactics, while the Russians had no records of their service. The Free French were supplied with them, and most notably killed a Panzer V during the Liberation of Paris. The British developed their own variant, the Achilles, which put the QF-17 Pounder in the M10 chassis. Audie Murphy earned a medal of honor using the M21918 MG to hold back German soldiers while using the radio to call in artillery barrages on a wrecked Wolverine.

Near the end of the war, the M10 was increasingly obsolete, and desperate attempts to keep the vehicle viable in combat service included strapping sandbags and lumber to the outside for extra protection. It also had a hand traversed turret, something that was increasingly obsolete in the latter part of the war against the modern and more efficient electrically traversed Panzers. It was largely replaced by the M-18 and the M-36 by the end of the war, but was kept on due to the sheer number of them and ease of repairability.

Some were exported to nationalist China, but these were obsolete on arrival and were replaced by captured Japanese surplus material.