The cable has a USB A plug at one end and a USB A socket at the other. Usually, it connects an A socket on your computer or your hub to the A plug on the device's normal cable.

The plug mouldings and the double-shielded cable are beige-grey, with red cable collars. The choices are 2.0 metres and 3.0 metres: 3.0 metres is nearly 10 feet

USB 2.0 specifies a maximum single-run cable length of 5.0 metres, unless you use a hub as a booster: a signal integrity limitation explained on the technical page.
Because an extension is designed to extend an existing cable, they are not made in 5.0 metre lengths as the combined length would exceed the 5.0 metre limit.

They're top quality cables: they look it and feel it, and their manufacture and testing comply with ISO 9002 standards. They're very robust, and are guaranteed for a year against faulty manufacture.