They have rubber wheels and so far I have only used them on the indoor cement rink. I would like to use them both in the rink and on the sidewalk. Will this hurt the wheels?
It could be a smoke detector that needs it's battery replaced. Other thoughts are banging pipes, slow water leak onto a metal surface or some kinds of rodent? Sounds weird though.
translucent, typically. But you can really use anything, depending on the type of light quality you want to let in (or don't want to let in). I've seen different styles of glass mixed.so there really is no right answer.
