Weather Seals for FortiAP 112D

My FortiAP-112D has two holes at the bottom of the housing for Ethernet cables, each about 11/16" or 18mm.  These were supposed to have weather seals, judging from the image on the cover of the QuickStart Guide.  Due to the way the bottom cover slides into place, a standard cable gland out not work.  Maybe some molded rubber piece was used.

Can anyone advise what sort of seal to use and/or where to find it?

Thanks,

billvo