The strips are available from the kit manufacturer or supplier.
Backs supplied by kit manufacturers are often made of cardboard.
Puma were announced as the new kit manufacturers for the 2010-11 season.
But kit manufacturers say they are also less encumbered by a corporate culture used to making airplanes one way.
The kit manufacturer estimates the construction time at 1000 hours.
A table of kit manufacturers (since the 1970s) and shirt sponsors appears on the right.
Adidas were announced as the club's official kit manufacturer for five years.
However, only one main sponsor is permitted per jersey in addition to that of the kit manufacturer.
Nike are the kit manufacturers, the only sponsor is Kyocera.
The club have had a lot of different kit manufacturers since the 1970s.