During World War I, in which the Netherlands were neutral, some 100 Spyker fighter aircraft and 200 aircraft engines were produced. In 1919, after World War I, a two-seater car, the C1 "Aerocoque", featuring aerodynamically streamlined bodywork influenced by aircraft design, was shown for the first time. It was intended as a show car, but was also produced on a very limited scale. The car's bodywork, featuring swooping fenders and an aircraft-like tail, infused by the company's knowledge of aircraft aerodynamics, was mainly designed by Jaap Tjaarda van Sterkenburg, brother of John Tjaarda and uncle of Tom Tjaarda, both also car designers. On November 27, 1920 the first Spyker 30/40HP C4 was completed, sporting a 6-cylinder Maybach engine of . The car was nicknamed "Tenax" (latin for "tenacious") and improved the long-distance endurance record, held since 1907 by the Rolls-Royce Silver Ghost by some 6,000 km. The C4 completed 30,360 km in the Dutch winter weather in just over a month. In 1922, racing driver Selwyn Edge took to Brooklands in a Spyker C4 fitted with streamlined racing bodywork, setting a new "Double 12" average world speed record, covering 1,782 miles (2,868 km) at an average speed of for the 24 hour aggregate of two 12-hour periods. Also in 1922, the company went bankrupt again and was acquired by Spyker's distributor in Britain, who renamed the company Spyker Automobielfabriek. Production continued and prices dropped but the company continued to decline. Final production was of the C2 two-ton truck and the C4 car, which lasted until 1926 when funds finally ran out. It is estimated total Spyker car production was at most 2000 cars. In 1999, a new company, Spyker Cars, was founded, unrelated to the original company but for the brand name, motto and logo. License production and auto rental Before Hendrik-Jan Spijker's death, he and his brother had developed a special relationship with Dutch electrical pioneer, Rento Hofstede Crull. The Spijker brothers had known Hofstede Crull already when he was a young man racing on the velocipede circuits in the Netherlands and in Germany while he was an engineering student first in Mittweida and later in Hannover at the Technische Hochschule in the 1880s. Hofstede Crull had already owned his first automobile in the 1890s. In the first decade, he had accumulated a collection of automobiles which included a number of the Spijker racing models. He housed the collection