
Contrary to an answer to my only question on the product page, they can be filled with loose fill and do not require a specific size pillow inserts. But the cost of buying the stuffing separately is almost the same as the inserts. But in my case I took 3 or 4 smaller pillows, mixed all the filling for constant firmness and filled them with almost free filling. I ended up needing a lot less filling than I thought to get the hardness I wanted. So now I have enough left over to save for many future pillows.

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