AirCraft AT0016-40 Block Ring For Air Ratchet Wrench

At a Glance: Replacement block ring (retaining circlip) for the AirCraft AT0016 air ratchet—keeps key components securely located under vibration and load.

If you’ve ever opened a tool and found a “mystery ring” missing… that ring usually wasn’t optional. The AirCraft AT0016-40 Block Ring is a replacement retaining ring (circlip/snap ring style) used in the AirCraft Air Ratchet Wrench (AT0016 series) to hold components in their correct position within the assembly. It prevents axial movement, keeps stacks seated, and helps the mechanism maintain correct clearances while the tool is working under vibration and torque loads. A worn, bent, or fatigued retaining ring can lead to excess play, rough operation, or internal parts shifting out of place. Replacing the block ring restores secure retention and helps keep the ratchet running smoothly and reliably.