XTZ farm tractors by series

The Kharkov Tractor Plant (XTZ) is a Ukranian manufacturer of tractors, including large four-wheel drive tractors and crawlers. The Kharkov tractor factory was founded in 1931, initially building a 30-horsepower farm tractor and then a 52-horsepower crawler tractor. Production of the 150K series four-wheel drive tractors began in 1973, a series which has been exported worldwide and continues in production.

XTZ - official site