Volvo Penta Early D3 series and some AD31, AD41 series Air Filter for diesel engines. This is a round filter and not the square version
To tell the difference, for a AD31 or 41 series which may use either part, part number 858488 has a screw on air filter cover and 21646645 has a clip on cover.
Volvo Penta Part No: 21646645
For: D3-130A-A, D3-160A-A, D3-110I-A, D3-130I-A, D3-160I-A
For: Some AD31 Series, Some MD31 Series, Some AD41 Series, Some TAMD41,