Later German tanks received a new designation, "Panzerkampfwagen" (abbreviated to 'PzKpfw' or 'PzKw' in German and 'Panzer' in English), which means "armoured fighting vehicle". The first machine to use this was the two-man Panzer I "Ausf A" influenced by the Carden Loyd tankette, and was a 5.4 ton machine with a 3.5-litre 60 hp (45 kW) petrol engine. It had 13 mm of armour and was armed with twin 7.92 mm machine guns. The more common Ausf B was a little larger to accommodate a 100 hp (75 kW) Maybach engine. Both models were sent to the Spanish Civil War for testing, along with other new German weapons. From the experiences in Spain it quickly became clear that the next generation of tanks would need better armour, greater range and much heavier weapons.