Agilent Technologies 1660A Series User Reference page 34

Probing
Assembling the Probing System
Connecting the Grabbers to the Probes
Connect the grabbers to the probe leads by slipping the connector at the end
of the probe onto the recessed pin located in the side of the grabber. If you
need to use grabbers for either the pod or the probe grounds, connect the
grabbers to the ground leads in the same manner.
Connecting Grabbers to Probes
Connecting the Grabbers to the Test Points
The grabbers have a hook that fits around the IC pins and component leads.
Connect the grabber to the test point by pushing the rear of the grabber to
expose the hook. Hook the lead and release your thumb as shown.
Connecting Grabbers to Test Points
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