A previous study evaluating the mothproofing activity of synthetic pyrethroids of the type 2‐substituted 3,3‐dimethylcyclopropane‐ 1‐carboxylates found this class of compounds to be active against the common clothes moth (Tineola bisselliella H.) and the black carpet beetle (Attagenus piceus Oliv.), but higher concentrations were required to protect keratinous materials from larval damage by the furniture carpet beetle (Anthrenus vorax Waterh., syn. Anthrenus flavipesie Conte var. seminiveus Casey). The present paper evaluates the mothproofing efficacy of the structurally related α‐substituted phenyl‐acetates. It has been found that this class of substances exhibits an activity pattern that is similar to that of the 2‐substituted 3,3‐dimethylcyclopropane‐ 1‐carboxylates. A representative of the phenylacetate class, S—5439, is compared with the corresponding cyclopropanecarboxylate, permethrin.