3545586, Volvo 850, S70, V70, C70, o ring seal kit between the Heater Core and the connector pipe , for the 9144221 Heater Core. The seal kit has 2 (two) o-rings
When replacing heater core these should be changed. The heater cores that we sell do come with the new o- rings.
We offer these o-rings for the people that have purchased heater core at some other place and o-rings did not come with the heater core.
If you simply want to replace the o-rings between the heater core and the connecting pipes these are for your Volvo!
these o- rings will fit

Volvo 850 1993-97,
Volvo S70 1998-00,
Volvo V70 1998-00,
Volvo C70 1998-04