We have been unable to obtain any more of the dryer felt we used to sell for use in paper drying stacks.
We have a replacement material which is also spin-bonded polyester, but it has only about half the weight per unit area compared to our old felt. On the other hand it has a much higher loft: its uncompressed thickness is about 2cm (¾″).
If you clamp your drying stack tight enough this will flatten out like the old felt did, but by leaving the clamps or straps a bit looser, this felt will remain open, thus allowing more air circulation closer to the paper. The higher loft also means that the ridge pattern on the corrugated dryer boards will be less likely to transfer to the dried paper.
One downside is that the higher loft makes for bulkier parcels and higher shipping costs on orders.
Finally, the new felt is 90″ (229cm) wide, giving a little more versatility for cutting to size than the old 60″-wide felt. We sell it in cut lengths at $4.90 per linear metre.