Exterior install. Bare concrete. Installed three years ago with about 100 others. Some inside, some outside, all exposed to the elements. Tape and silicone. Still up.
Exterior install. Bare concrete. Installed in January 2017, so it's been up for 6 years. Tape and silicone. Still up.
Multiples of these installed a few years ago with tape and silicone. Still up.
Heavy stainless steel plaques installed with tape and silicone in February 2020. Exterior. Still up.
That was like a 5 minute search through pics. I install multiple parking garage
sign packages every year with hundreds of tape-mounted panels at each one. It's almost always on bare concrete.
Pretty sure if a 5' wide aluminum panel sticks in place, his little 2" x 5" panel will stick.