Though similar to a carabiner, a quick link uses a threaded sleeve closure instead of a gate for a more secure connection. These are made from stainless steel for strength and corrosion resistance.
The set of seven pieces includes two 4mm × 30mm (wire diameter by inside length), two 5mm × 40mm, two 6mm × 47mm and one 7mm × 52mm link, and comes on a 3" diameter aluminum carabiner.
Dimensions noted are nominal. Not for use where disengagement could result in injury.