Verify that the moving side-piece is properly engaged on the cam axle. Danger of death if it is not properly engaged.
Inspection, points to verify
Verify that the moving side-piece is not deformed and that it is not loose enough to be closed without properly engaging the cam axle (the sidepiece should not be able to pass over the flange at the end of the cam axle).
The test consists of verifying that the moving side-piece cannot be closed without properly engaging the cam axle.
To avoid damage to your device
While carrying the device, for example on a gear loop or harness attachment point, the moving side-piece should always be closed on the carabiner.
Information is non-exhaustive, refer to the Instructions for Use and other I'D EXPERIENCE documents.
Check also the I'D product data sheet.