NEMO Equipment GOG - Manual (Page 6)

4. Swallowtail: The reinforced pocket on the
Gogo™ foot end provides a place to insert a stick
or other rigid object. With the stick in place, the
Swallowtail patterning causes the entire bivy
to tension. This will help keep the bivy off your
sleeping bag and promote better air circulation.
Gogo™ can be used without the stick and simply
behaves like a traditional bivy.
5. OSMO™: Revised for 2010, NEMO’s improved
waterproof/breathable fabric, OSMO™, continues to
set the standard for breathability in single wall tents.
The new OSMO™ is a 40D ripstop polyester with a
hydrophobic microporous PU coating. The polyester
is naturally UV-resistant and doesn’t sag when
wet. OSMO™ is highly durable, chemical-resistant,
lightweight, and abrasion-resistant.
6. Watertight Compression Sack: Many of the
NEMO tents include watertight dry bags, including
Gogo™. Having your tent in a watertight stuff sack
means it won’t take on water weight if it’s in your
backpack while you’re hiking in the rain, or if it’s in
your kayak when you roll your boat. Alternatively,
if you have to pack your tent wet, it will help keep
the rest of the gear in your pack dry.