By July, the La-5 was ordered into full production, including the conversion of incomplete LaGG-3 airframes. Production based on the prototype began almost immediately in factories in Moscow and the Yaroslav region. Changes to the main production model included slats to improve all-round performance. The La-5 was inferior to the best German fighters at higher altitudes, but equal at lower altitudes; it was suitable for air combat over the Eastern Front which typically took place at altitudes under 5,000 m (16,404 ft).