Directions of Dekko Silverfish PacksPlace two to three Dekko Silverfish Packs in each infested area. Place in closets, drawers, bookcases, in basement and dark hidden places. Also in areas where silverfish inhabit, under house and in attic if possible. When Dekko Silverfish Packs are used as the only treatment, control may not be obtained from three days to four weeks, depending upon conditions. Repeat treatment as necessary to affect and maintain control. Replace every three to four months from date of purchase.