Looks like stainless steel. I don't know off-hand where to get it, but if you didn't mind a more matte finish, aluminum angle might work. It is readily available at most hardware and big box building supply stores.
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A good silicone will work… 2-4” is not going to stop a ray from bailing tho… $500-800 on the floor isnt a fun experience. Id still go with lids over top weighted or clipped down.Any recommendation on mounting to glass?
