These are high-density blocks balsa wood that can be charged with abrasive pastes for the purpose of sharpening straight razors.
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LAVODA 6pcs Leather Strop Polishing Compound Kit 3 x 11 Premium Balsa Strop Leather Strop with 3 Micron & 1 Micron Polishing Diamond Paste, Magnetic Backed Strop Base for Sharpening Knives
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