Football Jumpers offer companies who pay for sponsorship a high profile mobile billboard facility .
Companies pay highly to have their company name emblazoned on the clubs gear .
The companies consider it worth the expenditure as they receive high visibility for their product.
Sponsors come and go .
A jumper can be dated by who the sponsor was at the time .
Often fans or collectors will seek out a specific jumper with a unique sponsor because it triggers a memory or reminds them of a favourite place in time.