You can easily renew your denim using Tintex and the hand dyeing method (or use the washing machine). If your jeans have faded evenly you can simply over-dye
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Add vibrancy and color to your fabric projects with the Dylon Permanent Fabric Dye 1.75 oz. This pack includes 1.75 ounces of permanent fabric dye in a spill-free plastic envelope. It has been specially formulated for hand dying in warm water and is suitable for all natural fibers and polyester cotton blends. The colors of this fiber-reactive fabric dye don't fade or wash away over time. Choose from a variety of beautiful shades that are available.
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