AustriAlpin
Rondo HMS Slide Lock

Technically the locking piece pivots rather than slides into the unlocked position. I've included this carabiner in the slide-lock category because the user interacts with the protected locking piece much like a slide-lock mechanism. The short pivoting action, combined with an angled upper surface and light spring will permit the user to unlock the carabiner gate with a direct press on the upper angled surface - no sliding needed.

While undoubtedly more secure than a non-locking carabiner, I would not consider this as secure as other single lock auto-locking carabiners in applications where something small (or squishy) could get pressed against the gate. That said, the locking piece is somewhat protected, and may be more secure than other slide-lock carabiners such as the Edelrid Pure or Petzl Vertigo when pressed against tensioned rope or similar.

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