Volvo Heater Core/Hose O Ring - Santech 3545586

These were excellent and extremely high quality for aftermarket. Use outright or keep some around for spares. Great price for back-up.

Good Fit. No leaks after a few weeks installed. I will update if I have any premature failures from them. so far, I'd buy them again.

very affordable, fit tightly and don't leak, always keep some spare ones lying around

Just installed the O-rings to the heater core. So far there are no leaks!

quality looks good, but ended up not installing them and going with OEM

They work fine. I should have bought 4. While trying to disconnect the inlet tubes from the core I snapped the plastic at the firewall. Had to call every dealer in town and nobody had one BUT the dealer I normally go to suggested an Advance Auto parts about 1/2 hour from me. I called them and they had one- someone was watching over me today. If anything could go wrong with my heater core replacement it did. Getting the inlet tubes into place and screwed in was a royal B. I haven't been that pissed off in a long time. In the end, once I got the inlet tubes connected to the firewall and then got the heater core installed and everything put back together, I filled up the coolant and let the engine warm up to operating temperature hoping for no leaks. Seems to be nice and tight and blows hot air considering how cold it is outside. I wish FCP had a warehouse and store in Colorado. For a car that's 23 years old, I shouldn't be surprised that the plastic was that brittle.

99 V70 FWD Manual 2.4L Non-Turbo Good Fit, Easy Install

Worked well - no leaks.

Just did a heater core replacement and ordered six of these o-rings to have on hand. They were slightly thicker than the ones provided with the core which seems to be consistent with them being the same dimensions as the Volvo rings. They appear to be well formed and made from good material. They fit as they should and seal properly. High confidence in these.

Replacing these solved the mystery of the disappearing antifreeze and cleared up the intermittent whiffs of coolant in the passenger compartment.