which one should I use to kill house centipedes & spiders?

There is no such bomb that will get rid of centipedes or spiders. We recommend Suspend SC which is a liquid concentrate that is diluted in water and sprayed on surfaces like the baseboards, under and behind the furniture, the window sills and etc. All treated areas should be avoided until it is completely dry. You do not need to remove the bed mattress as this is not the primary area that centipedes will hide. If you have any further questions or comments, please feel free to contact us again.