Microballoons are expanded glass beads, microscopic in size. They are so small; they have the appearance of powdered sugar (but please donít taste them) and are extremely light. They make a strong yet lightweight putty when mixed with Cement (like Duco), Polyester Glass Resin, or Epoxy adhesivese. Instructions for mixing are on the container. They also make CAís instantly set… They are marketed to the hobby industry by SIG SIG Manufacturing Co.
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