A compact HMS karabiner, easily manipulated with one hand, its light weight makes it the ideal companion for mountaineering and rock-climbing.
If the screwgate is at all unscrewed a red colour shows to warn you to tighten it up.
This improved version has an H-shaped cross section which gives a better strength/weight ratio and wider contact surfaces for better rope glide and reduced wear. It also is slightly wider than its predecessor and has a wider gate opening.