I have had 4 of the rectangular (14 x 16") Old Stone Oven stones for about 15 or so years and have been very pleased with them. I often use 2 but can use 3 at a time in my oven (they are a huge heat sink, so I preheat 1 1/4 hours at 550 degrees convection) but only use one on my grill.
Rita
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