Yeah, it's the thicker one, 10mm I think (it's green). It was $4sqm extra. There is a cat3 underlay (gold) which is the same thickness but is denser.
Thanks. $4sqm sounds ok. Does the 10mm thick underlay feel much difference? Is the standard 7mm?
I remember when we were at Cosham, there was a sample that everything could step on to get the feel of thicker underlay, and that one felt really nice. Was that the 10mm one?