This Columbia pillow. It has a cooler side, but I just use the regular one. My boyfriend and I think it's the best pillow we've ever owned. Kind of expensive, but it's well worth it.
It's $100 on Amazon, but this Columbia cooling gel memory foam pillow seems to work reasonably well for me as a side sleeper after a few years of use. I have to sort of shove it between my shoulder and head, vs. just lying down, but that's just become habit at this point.
I also find that the adjustable memory foam pillow that came with my mattress ends up sinking too much, and I have to keep flipping it sound.
I briefly tried the Malouf Z shoulder cut out pillow at a local mattress store and liked it so much I just ordered it. Here's hoping I like it, because I don't think it was returnable to the online store I found with a discount!
I guess it depends what type of pillow you are looking for but for my bed Ive used this one for years and I love it. My head usually gets hot and I have troubled sleeping. This one stays legit cool.
https://www.amazon.com/Columbia-Performance-Extreme-Cooling-Standard/dp/B07HGR92M1
This is my favorite pillow I've ever experienced. It has a cool side, but I always use the regular one.
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