Although most at home test kits will have a single UDI for the "test kit" (all in one package of reagents, test card/device, etc.) it is possible for at home kits have a resuable "reader device" which would need the distinct "equipment id". An example of this is Cue Health's devices here: https://shop.cuehealth.com/products/bundle-3-pk where a single reader "device" is re-used," with a new "test kit of cartridge and wand" each time.   In this case, the reader device would have an "equipment UID" that may be the same for multiple tests performed. For these cases we will map the Equipment UID to Device.udiCarrier.deviceIdentifier and give guidance on using multiple Devices - one to represent the test kit (which would have the Test Kit Name ID mapped to Device.udiCarrier.deviceIdentifier) and one to represent the reader device (which would have the Equipment ID mapped to Device.udiCarrier.deviceIdentifier). See the following links for reference: Expand documentation tab on link to see test documentation/info: https://cuehealth.com/help-and-support/product-documentation/?_ga=2.91583258.187071539.1671735425-1062822349.1671735425 and instructions: https://cuehealth.com/documentation/home-otc/Cue_COVID-19_OTC_Test_Instructions_For_Use_(IFU).pdf