Petzl's Sm'D asymmetric D-shaped carabiner for vertical workers looking for maximum lightness. Its shape and dimensions make it useful for multiple uses, at the same time it is one of the strongest and lightest carabiners designed by Petzl. The "D" shape offers the best strength to weight ratio.
The Triact−Lock system is a three movement automatic locking system. The keylock system prevents any inadvertent hooking of the carabiner.