The Extra Flugzeugbau Extra 300 is a competition-level aerobatic monoplane aircraft. Designed by Walter Extra, a retired aerobatic pilot, in 1987. It has since evolved into an even higher-performance single-seat version (300S/330XS) and has been updated to make use of composite technology.

The aircraft is based on a welded steel tube fuselage covered in light alloy and fabric. The mid-set wing is fully symmetrical, made of carbon composites under fiberglass shells. The landing gear is of the fixed taildragger type with the main unit of composite construction with fiberglasss wheel pants.

The Extra 300 is stressed for +-8G, while the 300S/L are stressed for +-10G. The Extra 300L is a two-seater variant of the 300, with its wingspan reduced from 26ft 3 in (8.00 m) to 25 ft 3 in (7.70 m). Improved ailerons boost the 300L's roll rate to 400 degrees per second. The 300S had its wingspan reduced by 1 ft 7 1/2 in and was also fitted with larger ailerons. The Extra 330 is a development of the 300S, with a wider-chord rudder, and a more powerful Lycoming IO-580 powerplant producing 330 hp (246 kW).