Dont take it to your heart and listen to sound advice,the past posts only mildly mock and forewarn you of the perils of kit not fit for purpose especially when the instructions for said kit are very hit and miss.The type of kit you are referring to are basically OK as a hobby type of detection ,checking your own room or office,something your wife or partner in a business might have planted,in other words the type of equipment you can buy off the shelf to covertly film or listen to can be detected with a bit of practice by a self learner,remembering that to try and detect these pieces you also have to buy them as well as your detector,remembering the frequencies and the activation of dormant devices that could be hidden by a friend or colleague for you to find with your off the shelf detector.All this is well and good for personal and domestic situations ,even on low threat/risk visited hotel rooms offices for piece of mind coupled with a well planned sectioned physical search of location but when you transpire to corporate and risk searches of Principals residences/embassies/Mil attaches and so forth ,the technical and expertise of the professional planter must be matched by the search teams using scanlock and associated kit costing thousands and is only as good as the operator and his training,also remembering that once searched it is only as cleared as it is ongoing,unless sealed and never entered into again the risk is always there ready to have a plant yet again.There is always a way as the old saying goes "OK when last searched".