R4
- 4R (disambiguation)
- BBC Radio 4
- Bisnovat R-4
- Caudron R.4
- Colin McRae
- Curtiss Model R
- DVD region code
- Exotic R4
- Ghent
- Group R
- Jaguar R4
- List of R-phrases
- Philippine Marine Corps
- Plan R 4
- R-4 motorway (Spain)
- R4 (Canberra)
- R4 (New York City Subway car)
- R4 (RER Vaud)
- R4 (Rodalies de Catalunya)
- R4 41st Avenue RapidBus
- R4 assault rifle
- R4 cartridge
- R4 expressway (Czech Republic)
- R4 expressway (Slovakia)
- R4 nuclear reactor
- R4 road (Zimbabwe)
- Radial Road 4
- Regjeringskvartalet
- Remington R4
- Renault 4
- Rush Rush Rally Racing
- Sikorsky R-4
- Suzuki GSX-R/4