The Monterey Spider Trap effectively controls spiders without the use of insecticides. Each box contains 4 ready-to-use traps that are moisture-resistant. The traps are completely non-toxic and safe for organic uses. The traps should be placed evenly along in areas where spiders have been seen, such as along baseboads, in doorways, and in dark areas. For best results, the side of the traps should always be against the wall. Traps should be replaced every 2-3 weeks.