The Char G1P, put forth by SEAM ("Société d'Études et d'Applications Mécaniques"), had received its designation letter P because Poniatowski had designed it. SEAM was the only company whose project was sufficiently advanced – due to it being informed in advance of the first specifications of 1935 – to present an actual prototype to the "Commission de Vincennes", early in the night of 3 December 1936, albeit in an unfinished state. Despite having neither the intended engine nor any armament fixed (a bell-shaped dummy turret with large glass windows was placed on the turret ring), the vehicle already weighed 23 metric tonnes, confirming the prediction of a study made by the army workshop, the "Atelier de Rueil" (ARL), that it would be impossible for a tank to meet the required specifications within even a 28 tonne limit. Instead of the intended 12 CV 280 hp engine a Hispano 6 CV engine of 120 hp had been utilised. Although a petro-electric transmission system was used, theoretically leading to a higher effective power output, tests performed between 3 and 10 December showed that the maximum speed was, as could be expected from the weak provisional engine, a disappointing fourteen km/h on the road, and ten km/h in terrain. The transmission alone weighed 2.4 tonnes, 1.5 tonnes heavier than a traditional mechanical system. Steering was easy though, and unlike most other petro-electrical systems it performed without reliability problems. The vehicle made extensive use of smoothly curved cast sloped armour. There was room in the right side of the hull for a 75 mm main gun. There was to be a crew of four: a commander (also manning a machine gun turret), a driver, a gunner and a radio-operator. The length was 557 cm.