 Collar number

A collar number, also known as a shoulder number, force identification number (FIN) or occasionally as force number (although this can also refer to the ID number of a force itself), identifies police officers, police community support officers (PCSO), special constables (SC or SPC) and some police staff in UK police forces - other law enforcement agencies, such as Immigration Enforcement, have also adopted identification numbers.Although now displayed on epaulettes (i.e.