The FV 620 Stalwart, informally known by servicemen as the 'Stolly', is a highly mobile amphibious military truck built by Alvis

Alvis Cars

Alvis Car and Engineering Company Ltd was a British manufacturing company that existed in Coventry, England from 19191967. In addition to automobiles designed for the civilian market, the company also produced racing cars, aircraft engines, armoured cars and other armoured fighting vehicles, the...

 that served with the British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

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The Stalwart was a private venture by Alvis that was adopted and entered service with the British Army

British Army

The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...

 in 1966 as a general transport truck in preference to the FV431, the load carrier variant of the FV430 series

FV430 series

The FV430 series covers a number of armoured fighting vehicles of the British Army, all built on the same chassis. The most common of the series is the FV432 armoured personnel carrier....

. It was one of the same line of vehicles that included the Alvis Saracen

Alvis Saracen

The FV603 Saracen is a six-wheeled armoured personnel carrier built by Alvis and used by the British army. It became a recognisable vehicle as a result of its part in the policing of Northern Ireland.-History:...

, Saladin

Alvis Saladin

The Saladin is a six-wheeled armoured car built by Alvis, and fitted with a 76mm gun.Used extensively by the British Army, it replaced the AEC Armoured Car that had been in service since World War II.-History:...

 and Salamander

Alvis Salamander

The Alvis Salamander is a 6X6 Airport Crash Tender with off-road capabilities, developed in 1956.It shares the same common six-wheel-drive chassis and other components with the FV 601 Saladin armoured car and FV 603 Saracen armoured personnel carrier...

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