European category under EASA - European counterpart to the FAA. It may aply only to certain countries.
Basic definitions of the CS-LSA (EU):
A Maximum Take-Off Mass of not more than 600 kg (1320 lbs) for aeroplanes not intended to be operated on water or 650 kg (1433 lbs) for aeroplanes intended to be operated on water.
A maximum stalling speed in the landing configuration (VS0) of not more than 83 km/h (45 knots) CAS at the aircraft’s maximum certificated Take-Off Mass and most critical centre of gravity.
A maximum seating capacity of no more than two persons, including the pilot.
A single, non-turbine engine fitted with a propeller.
A non-pressurized cabin.
Lots of European CS-LSA airplanes qualify as an light sport aircraft in the U.S..