We spent hours poring over child safety catalogs, looking through stores, and reading articles about how to child proof our fireplace hearth, as well as many other parts of our house.
This type of fireplace guard was one of the things we considered, but we had heard and seen too may of the same problems: not enough adhesion, attractive nuisance, etc.
I decided that our children's safety was worth more than what the potential downside on looks would be, and came up with a "home-grown" fixit: duct tape and pipe insulation. For a total of about $6.00, I purchased some foam pipe insulation (the type that is slit on the side, and comes in 3' lengths, to be slipped over piping for thermal protection)and a roll of good quality duct tape.
You can easily cut the insulation to fit (the inside diameter can be purchased to meet your needs...we used 3/4") your hearth, and with a little patience, each piece can be taped in place temporarily. After all are in place, 2 or 3 layers of duct tape can be overlaid to ensure wrinkle-free coverage, and good adhesion to the hearth surface.
With some of the newer tapes available, you may even be able to match your decor, to some degree. Heck, at this cost, you can afford to change the guard seasonally!
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