You are most likely looking at a mount for some type of instrument that has a suction mount, like a GPS, or tire pressure system.
If you can post a pic it will help.
Tony & Ruth........... FMCA#F416727
2016 London Aire 4519, Freightliner chassis, Cummins ISX, 2018 Jeep Wrangler Unlimited, Blue Ox Avail with AF1. TST 507 TPMS