A carabineer is a loop made of metal with a spring loaded gate. Ok, now that we have that figured out, let’s move on. It is used to connect components, especially those used in safety systems. Snaphooks are also similar to carabineers, but are usually much more robust. The two common materials of carabineers and snap hooks are aluminium and steel. There are many different gate sizes depending on what you’re attaching to. For example most rebar snap hooks have a 2 ½ inch gate. The new Z359.1, Z rating standard requires snap hooks and carabineers to have a gate face and gate side that will withstand a load of 3,600 lbs. and a tensile load that will withstand a load of 5,000 lbs. Z rating will be marked with a Z.