The SPIRIT set THE STANDARD as the perfect carabiner when it first came out and over the years it has been refined into the current lightweight at 39 grams and increadably strong design. This version is the 3D design - saving even more weight in key areas, yet maintaining the same ideal size and high strength ratings.
Keylock provides the "clean nose" design that prevent snagging on ropes and slings.
When combined with the straightgate model, these make the perfect quickdraw.
These are one of the best climbing investments you can make on your rack.