• Full thickness sponge is medium-soft foam with abrasive surfaces on 4 sides
• High flexibility sponge is very soft foam with abrasive surfaces on 3 sides
• Fine Grade sponges feel like approx. 100 grit
• Medium Grade sponges feel like approx. 60 grit
• Can be used wet or dry
• Size is 3-3/4"L x 2-5/8"W
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