Centaur.

This is coolbert:

Centaur = FV4005. Cold War British tank destroyer. 

"A tank destroyer, tank hunter, tank killer, or self-propelled anti-tank gun is a type of armoured fighting vehicle, armed with a direct-fire artillery gun or missile launcher, designed specifically to engage and destroy enemy tanks, often with limited operational capacities."

British response to the Soviet era JS-III main battle tank. 

Limited capacity to say the least. More like a ponderous contraption "operational capacity" far less than might be expected. See the You Tube video, the FV4005:

Comments:

* FV4005 not a tank. A tank destroyer. See above definition. Not an all-purpose armored fighting vehicle.

* That turret providing protection against small-arms fire only. Apparently a round from a Soviet era anti-tank machine gun could penetrate the "armor" of the turret.

* High-Explosive Squash Head (HESH) round the only ammunition fired by the main-gun. The crew needed to be persons resembling a minor Hercules to load both the shell [160 lbs. (72.5 kg)] and propellent [73 lbs. (33 kg)]. FV4050 carrying only a very limited load of twelve rounds.

* FV4005 strictly to be found only in the rear-areas of the combat zone? FV4005 used primarily to thwart a Soviet-style breakthrough offensive effort spearhead by massive numbers of tanks.

See further another You Tube video simulations of the 183 mm FV4005 HESH round striking a Soviet T-54 tank.

"FV4005 vs T54 | 183mm HESH Simulation | Overpressure & Armour Piercing S..."

"The 183mm HESH of the FV4005 was designed to knock out any Soviet tank of the 40's and 50's with a single hit. The massive 72kg HESH projectile had enough explosive mass to perforate around 75mm of steel, while being able to create spalling through plates exceeding 200mm thick."

Only two prototypes of the FV4005 built. Further development obviated by the coming-of-age of the anti-tank guided-missile of the British Malkara type.

coolbert.