The ALCO Filters MD9504 air filter is designed for the BMW 3 Compact E46 and filters the air entering the engine. It is compatible with the 120 d 1995 cc 120 kW, 118 d 1995 cc 90 kW, 318 d 1951 cc 85 kW, 318 d 1995 cc 90 kW, 320 Cd 1995 cc 110 kW, and 318 td 1995 cc 85 kW engines in 2003–2005 models.
- Type: Air filter
- Compatibility: BMW 3 Compact E46
- Engines: 120 d 1995 cc 120 kW, 118 d 1995 cc 90 kW, 318 d 1951 cc 85 kW, 318 d 1995 cc 90 kW, 320 Cd 1995 cc 110 kW, 318 td 1995 cc 85 kW
- Model years: 2003–2005
- Height: 377 mm
- Outer diameter 1: 143 mm
- Outer diameter 2: 122 mm
- Inner diameter 1: 108 mm
- Inner diameter 2: 53 mm