Double back vs speed buckles
There is a warning sign “DANGER” on the buckle. The sign on the buckle is positioned in a way, that when the buckle is set properly, the sign is covered. If the sign is visible it means that the buckle is somehow not set properly and there is a danger of unfastening of the seat harness! The sign cannot be seen!
More modern version is so called quick-fastening buckle, sometimes also called QB (Quick Band). Strap is threaded through this buckle only two times. Part of the strap always stays in the buckle; strap is loosened only when it is necessary to putt the harness on or off. End of the strap has to be widened or otherwise fixed to prevent its slippage through the buckle. After putting seat harness on we pull at the strap and tighten it in the quick-fastening buckle.
Pros:
- Ease of putting on a ‘speed-buckle’ harness especially in colder temps. For me, no problem whatsoever with boots. I generally put my crampons on after harness but cant imagine it would make any difference to the ease of putting on the harness.
- Better use the elastic band to fix the end of the webbing to help the buckle do its job.
Cons:
- Some climbers do not fully trust the speed buckles, and knot the webbing behind the buckle, just in case.
- Sometimes you need a nut tool to separate the two buckles if the webbing was tightened.
Mountaineeringmethodology.com – harness
Outdoorgearlab.com – how to choose the right climbing harness