The "special ingredient" in a rodent-proof sheath is typically a material that has a strong, unpleasant odor that repels rodents such as mice and rats. Some common materials used for this purpose include capsaicin, the active component in chili peppers, and castor oil, which has a strong, pungent smell.

The effectiveness of a rodent-proof sleeving can be determined through a variety of methods, including field tests, laboratory studies, and customer reviews. In field tests, the sheath is placed in an area where rodents are known to be present, and observations are made to determine whether the rodents are repelled by the scent. In laboratory studies, the material can be tested to see how effectively it repels rodents in controlled conditions. Finally, our Rodent Resistant Braided Sleeves are effective at deterring rodents.