Acronyms and Initialism
- A
- AP - Admiralty Pattern (British Navy).
- B
- BR(S) - British Rail(ways) Southern Region
- BR(W) - British Rail(ways) Western Region
- BR(M) - British Rail(ways) Midland Region
- BR(Sc) - British Rail(ways) Scottish Region
- BR(E) - British Rail(ways) Eastern Region
- BR(NE) - British Rail(ways) North Eastern Region
- E
- E(as found on Pothead lids) - Ericsson Telephones Ltd (British Ericsson).
- G
- (G)PO - (General) Post Office
- GW(R) - Great Western (Railway)
- GCR - Great Central Railway
- L
- LE - Litholite Insulators Ltd.(GPO manufacturer code)
- LEA - Litholite Mouldings Ltd - Leicester (ex-Watford).(GPO manufacturer code)
- LMS(R) - London Midland Scottish (Railway)
- LNW(R) - London North Western (Railway)
- LR - Thomas De La Rue.(GPO manufacturer code)
- S
- SR - Southern Railway
- SS - Ebonestos Insulators Ltd.GPO manufacturer code)
- SSA - Ebonestos Industries Ltd - London SE15.GPO manufacturer code)