This paper model is a WWII 17pdr SP M10 Achilles (17 pounder, Self-Propelled, Achilles), a British variant of the American M10 tank destroyer armed with the powerful British Ordnance QF 17 pounder anti-tank gun in place of the standard 3" (76.2 mm) Gun M7, the papercraft was created by , and the scale is in 1:25.
With a total of 1,100 M10s converted, the 17 pdr SP Achilles was the second most numerous armoured fighting vehicle to see service armed with the 17 pounder gun, behind the Sherman Firefly.
The name "Achilles" was officially a designation applied to both the 3" gun and 17 pounder versions but was little used during the Second World War; at the time, the vehicle was called 17pdr M10, or 17pdr SP M10, or even occasionally, "Firefly". It has since become identified almost exclusively with the 17 pounder version. More information of the 17pdr SP Achilles at wikipedia.
You can download this papercraft model template here: WWII 17pdr SP M10 Achilles Tank Destroyer Free Paper Model Download