Dekko Silverfish Packs (4 Packs) Boric Acid 20.0% Dekko Silverfish Paks are to be used in residential housing (indoors and attics), basements, closets, bookcases, around household clothing and fabric containers, drawers, and also rugs and carpets. Dekko Silverfish apply at approximately 2 oz per 100 square feet or 1 quart per 250 square feet