(Minimum thickness of 9oz per square yard / 300g per square meter).
Using Terry cloth (think thin bath towels) reduces balls bouncing and rolling when they come out of modules.
A width of 45″ / 110cm will allow for full coverage of most tables with a pleasing overhang.
Note: Terry Cloth can be sourced under “Fabric by the yard/meter” at most fabric suppliers.
I have bought a couple of roles of this Terry cloth from Amazon and cut it into 6ft/180cm covers https://amzn.to/2KS9qyj (Paid Link Disclaimer), to hem the terry cloth I used Iron-On Fusing Web (hemming tape) https://amzn.to/2Gu4OZA (Paid Link Disclaimer).