This propeller and the aircraft for which it was made, the SE5A, were both designed by the Royal Aircraft Factory at Farnborough in England.

The aircraft was powered by the V8 200hp Hispano-Suiza engine which was designed by the eminent Swiss engineer Marc Birkigt, financed by a Spaniard, and although initially made in Spain was soon made under licence in France, followed by the USA, Italy, and Japan. This prop was made in England by Wolseley.
The Hispano-Suiza 8 was the most important allied engine of WW1 powering over half the aircraft operated by the allies. It was a 90° V8 with a single overhead camshaft for each of its two cylinder banks. The original design produced 140hp but continuous development resulted in late variants reaching 300 hp. The British version made by Wolseley eventually produced 200hp and was introduced in June 1917.
The data on the propeller reads;
200 hp Hispano Suiza The engine
T28096 The drawing number of the propeller
G355 N24 The 24th prop made in batch 355, which dates the propeller to about Spring 1918.

The propeller is in superb original condition and was lightly restored and polished by Aeroclocks. It measures 170 cm X 170 cm, with a depth of approximately 16.9 cm.