Compatibility with monitors

Hi Catherine, thank you for your enquiry, the Angelcare Monitor Sensor Pad must be placed directly on a solid surface under the mattress. the only mattresses it is not compatible with are hollow core & mattresses containing memory foam that will come into contact with the sensor pad. We hope this helps.  For further information on this or any of our other products available, if you follow the link https://www.babyonthemove.co.nz/store-locations/ this will take you to our online store finder. Here you can find contact details for your nearest Baby On The Move Store where one of our team experts will be happy to assist you in your product search and help answer any further questions you may have. We hope this has helped with your query.