The first armoured Jeep was developed very early on in the life of the Jeep, it was built by the Smart Company based in Detroit. They were well known as manufactures of armoured security vans. The model known as the T25 was based on the Willys MA it had the bonnet and radiator grill replaced with armour plating, the windscreen was also armoured with the addition of two slots which could be opened for driving, and two round holes to enable both the driver and the passenger to fire rifles through.
The Smart Companies armoured Jeep was delivered to the Army for testing in November 1941. The testing did not go well, although the armour plate was only 1/4″ thick the Jeeps suspension could not handle it very well. The prototype was returned to Smart’s for modifications, it was lightened and had armoured half doors fitted but the Army still thought that the weight was too much and needed to be reduced further.
The next version of the T25 had a lower windscreen with raked armoured doors level with the windscreen. Still retaining the round holes for rifles. The rear of the Jeep was still unarmoured. The Army considered that the vehicle was still over weight so it was returned to the Smart company for further modifications. 
The third version known as the T25 E1 was still based on the Willys MA. It featured full height doors giving more protection to the driver and passenger, but the rear of the Jeep lacked any protection. It was again rejected by the Army because of the extra weight.
The Smart company did not give up on the idea of building an armoured Jeep so in early 1942, they built another prototype based on the Willys MB. This was known as the T25 E2 the armour plating was now surrounding the whole Jeep, protecting the vehicle from the sides and rear. The Jeep now had nearly 1/2 ton of armoured plate which meant it could only carry a crew of three. This was quickly followed by the T25 E3 which instead of flat sided armour the plating had a V shape which improved its resistance to small arms fire. Visibility was improved by having three vision slots. There was one last version the T26 E2 which had a few small modifications. The Jeep was still considered unable to cope with the extra weight and project was abandoned in 1943
