RCS-8 (also known as 1-(2-cyclohexylethyl)-3-(2-methoxyphenylacetyl)indole, SR-18, and BTM-8) is a synthetic cannabinoid that has been found as an ingredient of "herbal smoking blends". It can be described as an analogue of JWH-250 with the 1-pentyl group replaced by 1-(2-cyclohexylethyl), and can be expected to be less potent than JWH-250. All CB₁ receptor agonists of the 3-phenylacetylindole class such as RCS-8 are Schedule I Controlled Substances within the United States.