Thanks for your interest! It is inexpensive shade cloth- the kind you can get at any big box home improvement center. Look for bolts of it for sale by the ft in the garden center.

Thank you - what do you think the durability is of this (especially east bay - 100 degrees in summer)

Can you suggest something more of a durable nature?

I find it to be very durable. It does photodegrade, but any polymer based outdoor fabric will. Other than that, it is weather proof.