Unique carabiner in "hourglass" design in which a simple wire opening isolates the belay loop and maintains the correct orientation even with the open carabiner. The shape guarantees the positioning of the carabiner automatically. Used for belaying and rappelling. Clepsydra is the arrival point of an analysis of the various problems that occurred in the belaying of a partner:

• Double opening with Twin-Gate system (Wire-Gate) to avoid the accidental opening of the carabiner "always and in any case"
• Flat in the lower part to follow the shape of the webbings of the belay loops, with "captive" safety wire to avoid "cross loading" or positioning along the minor axis of the carabiner, which would greatly reduce its strength
• Rounded upper part to allow easy movement of the device and the sliding of the rope / ropes if the tube is used, without edges which would ruin the ropes themselves
• External flap that prevents the device from getting sideways and working badly