frequently bear the letters SC (with or without a crown above) to differentiate them from regular officers. Within the City of London Special Constabulary is the Honourable Artillery Company Specials; members of this unit wear HAC on the shoulders in addition to other insignia. Senior special constables wear the same markings on their hats as equivalent regular ranks. There is a large variation in the design of epaulettes used across Great Britain for specials. This has been recognised at national level and as part of the Special Constabulary National Strategy 2018–2023 the structure and insignia is under review with the intention to standardise. Other special constabularies use combinations of bars, half bars, pips, crowns, laurel wreaths, collar numbers, force crests and the SC identity (with or without a crown) to distinguish ranks (and/or role). Miscellaneous police forces There are, in the United Kingdom, a number of miscellaneous constabularies. These are not operated, regulated or funded by the Home Office, although they are fully authorised (by Act of Parliament) establishments. In general, they provide the policing for ports, docks, tunnels, or other particular institutions. Although these forces tend to require high standards of training and accountability, which closely mirror those of the Home Office police forces, they are usually much smaller in terms of personnel, and therefore utilise fewer of the 'standard' ranks. Public order roles and rank insignia Officers taking part in public order and public safety (POPS) events and incidents wear colour-coded rank slides to denote command and support roles. Bronze commanders can be of varying ranks and not just chief inspectors as shown below. Tactical advisers can also be of differing ranks, but are most commonly constables or sergeants. It is a requirement under the College of Policing Public Order Manual that all officers, regardless of rank, display an identifying number on their epaulettes. Therefore, ranks such as inspector have collar/warrant numbers displayed on their public order colour-coded epaulettes that they might not have as part of their normal uniform. Police community support officers (PCSO) Police community support officers bear epaulettes with the words "Police community support officer" and their shoulder number, or, in the Metropolitan Police, a borough identification code and shoulder number. South Yorkshire Police PCSO supervisors wear a bar above the words "Police community support officer supervisor" and the shoulder number. Police cadets The following table serves as an example of ranks within volunteer police