Special Herbs, Vols. 4, 5 & 6 is an album of instrumental works released by MF Doom under the Metal Fingers moniker. As with the other installments of the Special Herbs series, each track is named for a herb (or similar flora) or herbal preparation, with the exception of "Coffin Nails" which could refer either to a slang term for tobacco cigarettes or literally to nails from coffins, which have been traditionally used in conjunction with certain herbs in the performance of ceremonial magic rituals.