Small flying insects, like whitefly, are attracted to these yellow pesticide-free traps, & then become completely stuck to the non-drying glue coating. However, unlike similar products the glue does not adhere to hands or clothing & prior to use has a 'cover' paper. The double sided trap works continuously for several months. Perfect for the greenhouse or indoors. Contains 7 greehouse fly traps plus hangers, each Approx. 10cm (4) x 24cm (9).