I got these to help monitor drain flies in my kitchen. They were recommended in the drain fly section of this site. Although there were some visible drain flies in the area, this trap didn't catch one. So maybe it was the wrong product for flying insects, I don't believe there is any attractant in these traps.
These monitor traps don't stay closed and they are much smaller than it looked on line and they are very easily to stick together once you have pulled the paper off to bend it the way it shows in the video and mash it across the glue strip they don't stick well and you get your finger caught in the holes trying to hold it down to close the monitor.
I am very disappointed in this product