Update 7/3/2022: It came time to replace the silverfish packets around our apartment about two months ago. It was easy to tell that it was time to replace them because we started seeing silverfish which we had not seen in months. I went to purchase these silverfish packets and they had gone up in price six times what I originally paid for them. Now that they are over $25, they are no longer worth the price and we would rather just kill silverfish when we see them scurry across the floor or hang out near the ceiling on the walls.Update 8/4/2021: We have these packets sprinkled around our apartment and have been seeing silverfish. Not a lot, only 3 so far, but we used to not see any when these packets were deployed. We even replaced them with fresh packets which did not help. I am lowering this review to three stars because I think they help but they no longer leave us with 0 silverfish.I live in an apartment and no matter how clean you are, if your neighbors have bugs you'll have bugs. Our neighbors apartment is crawling with silverfish. They started coming into our apartment on a regular basis. At the height of the infestation there were 6-8 silverfish a night in our bathroom.I've purchased these Dekko Silverfish Packs in the past and I knew that they worked. They contain 20% boric acid, something that neither silverfish nor ants like. There are 24 packets inside of the box. Silverfish will nibble at this packet instead of your stuff and then it kills them after awhile (not instantly by any means).Dekko Silverfish Packs last approximately 3-6 months depending on how bad your infestation is. At the height of our silverfish infestation they lasted 3 months and we only saw 2 silverfish in the entire 3 months. On a regular basis the packs last 6 months and could probably go even longer but we tend to replace them twice a year.To make these packs effective you have to know where to put them and how many to use. One pack in an infested spot is not enough. You need 2-3 packs in each infested area. So if you find them behind your toilet, drop three packs behind your toilet.We put 3 packs behind our toilet; 3 under our bathroom sink; 3 under our bathroom rug; 3 on each wall of our closet floor; and 3 underneath the dresser drawers inside of the dresser on the carpet. The packs are thin and you can literally drop them behind beds and furniture without moving any furniture around.The only way I know that these packets work is due to the lack of silverfish in the apartment. We do find dead silverfish on a regular basis, an average of 4 a week during our worst infestation, but they aren't crawling around eating our stuff anymore.To kill silverfish.Have not been able to find product in stores and good OLE AMAZON had it. the bestVery effective and easy to use!!I believe the product works. Since putting it down, have not seen a silverfish anywhere. Product must be doing it’s job.Silverfish and books are inseparable. Silverfish love magazines and newspapers, too. Where paper is stored, silverfish appear as if by magic. I can't stand having them pop out of a book that I want to read. There is nothing better than these Dekko Silverfish Packs for eliminating infestations. Put the packs around the house and forget about it. Dekko kills the silverfish. I put a note on my calendar to replace the packs once every three months. That keeps my house free of silverfish. Nothing could be easier or more effective.Recently had an influx of silver fish in my bathroom. These are easy to use-just lay down in the room you need them. They take a month or two to fully work, so in the meantime, I used Diatomecious Earth around the floor boards and that worked well, albeit a little messy. But once the DE dud its thing, I put these silverfish packs all around and haven't seen any in weeks. So I will leave these down at least until winter sets in. Recommend these, just be patient as they don't work overnight.Moved back to I left home for a few months, and when I got back, I saw a bunch of these disgusting silver bugs. Tbh I wasn't even 100% sure that they were silverfish, but I thought I'd go ahead and try these packs out. I don't know if they went away organically or if these packs took care of them but in either case, I'm not seeing them around anymore! Definitely worth a try :)This product has been around for years and I can only find it now on Amazon. The packets work well if you replace them once or twice a year, keep things dry - I use Damp Rid bags in almost every room/closet to collect moisture, and in closets I also add a moth product. Keeping things clutter free and as clean as possible helps a lot. Silverfish love moisture, paper, clothes and the dark. I still see one now and then, but with this product, their numbers have decreased very significantly.