ACR Electronics ARTEX GLOBALFIX V4 Quick Start Manual page 8

CATEGORY I BRACKET (For P/N 2830)
Category I Mounting Bracket – ACR P/N 2832
To mount the EPIRB in the category I bracket, insert
the top cap first at a slight angle and then press the
bottom casing until the EPIRB clicks and is firmly
supported. The EPIRB can only be mounted inside
the bracket the ON/Test buttons facing out.