Bose A20 Cannula Base

Designed for use with this boom-cannula refill, but an alternate base/attachment:
https://www.aircraftspruce.com/pages/fb/oxygen_aithre/aithreboomcannularefill_13-24377.php
https://aithreaviation.com/products/aithre-boom-cannula-longer-arm-refill

For use on the Bose A20, and with the mic on the left side of headset; a remix would be needed to invert it for right side use.

Two part print - assembled via a 8-32 screw and nut. A steel washer is recommended in the center of the joint for smoothness, and loctite on the nut to help retain tension when pivoting.

Screw holes may need minor drilling to match the screw used; clearance should be tight.

Double-sided adhesive tape is used on the flat portion of the cup to retain to the headset, similar to other commercial options.

Arm hole is sized for the white rubber/silicone tubing supplied in the refill kit; dish soap is useful to feed it through as the fit is intentionally tight for friction. Flexible arm will then insert into the tubi