Newbie question, knotty and dual knotty mods?

[franklin]

I'll get my first newbie question out of the way. Looking over Dutch's tarps I see "dual knotty mod" listed and in some threads I see knotty mod but no mention as to what it refers to?
So what is a knotty mod?
Thanks.

[calpal]

It's a piece of shock cord along the hammock hem where your head and feet go. It cinches up to create a footbox where the fabric would otherwise be flappy.

[Dutch]

Here is Knotty explaining it best....

[franklin]

Thanks guys. One down many more to go.