Polyester webbing works really great. Very little to no stretch and
doesn't abrade or absorb water like nylon. Don't get the real thick
stuff. Also, the polyester webbing works as your tree hugger as well
as the suspension. Form the webbing into a giant loop and girth hitch
to the tree with the free end hooked into the carabiner and then
tighten with a double ring buckle. In this manner you will have 2
lengths of webbing suspending the hammock from the tree, each with
half the load.
A double ring buckle works very good. As good as a cam buckle to
tighten. A little trickier to loosen, but once you learn the trick it
is easy and simple to loosen also. Also, the double ring buckle will
be a lot stronger than the cam buckle and won't have any abrasive
effect on the webbing like a cam buckle could.
I use 1,000 lb, 1" polyester webbing. These from Harbor Frieght:
work really great. Cut off the cam buckle and sew another loop in its
place with 2 rings in the loop.
I use the SMC descending rings. They're AL with a very high rated
capacity, light and cheap (about $2.50 each, you will need 4):
Using these, a double ring buckle will weigh only about 0.8 oz - good
even for those that watch their weight and the webbing is very light also.