We have a full 100% burn-in test during manufacturing. We perform a functional test before shipping. This test can take up to 30 minutes per product, as a specially designed system checks all aspects of iSocket performance based on extensive documentation. When you buy directly from iSocket Systems, our system verifies that the test has been passed. The product that did not pass the test cannot be sent - the system will detect and prohibit it. We pay particular attention to signal strength. We reject units if the signal quality is lower than usual for the area where we perform the test. If the product has a temperature feature and is ordered with a temperature sensor we test it and check that it shows temperature correctly. Then we also check the power outage feature for devices where this feature is available. Finally, we reset the device to the default and package it for dispatch. It is 100% guaranteed that you will get a tested and working product.