Sinclair Research worried that Clive Sinclair himself was using his own personal wealth to fund his inventions. By 1990 the company's entire staff had been reduced to just Sinclair himself, a salesman/administrator, and an R&D employee. By 1997 only Sinclair himself was working at his company. In 1992, the "Zike" electric bicycle was released, Sinclair's second attempt at changing people's means of transport. It had a maximum speed of , and was only available by mail order. Much like the C5, the "Zike" was a commercial failure, and sold only 2,000 units. In 1999 Sinclair released the world's smallest radio, in the
Prisoner transport vehicle escort high-risk transports. With this in mind, vehicles may also be equipped with radio communications, global positioning units, additional restraints and weapons, and other emergency equipment. To add additional security, prisoners are typically restrained while in transport and may be physically secured to the vehicle, handcuffed while in the secured area, or a combination of both. Prisoner transport vehicles may be operated by police services (see paddywagon), correctional services, field officers, court services, federal agencies such as the United States Marshals Service, or be contracted to private security companies. Prison buses were widely used in the late 1900's to transport