Degras is a greasy residue recovered from the scouring of raw wool, composed largely of lanolin-related compounds mixed with fatty acids and soaps. It is used primarily as a leather-softening and dressing agent, and in some lubricant and rust-preventive formulations. It should not be confused with refined lanolin, which is a more purified derivative classified separately.

Because these residues are byproducts rather than intentionally manufactured goods, suppliers should provide a process description or certificate of analysis confirming the material's origin as a residue from fatty substance or wax treatment. Without this documentation, customs authorities may reclassify the shipment as a refined fat, oil, or wax, potentially altering the applicable duty rate.