Question:
May this sponge be used on Shabbos? The inside is a hard "plastic" spread very far apart, but the outside looks like a regular sponge. I see that some rabbonim give a "hechsher"--- I am asking your opinion l'halocha.
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Answer:
What are the reasons that the Rabbonim give a hwechsher and why do you think it might be a problem?
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