If you received additional Sensor Dots or Cradles to use with your Byteflies Kit, please review the relevant information here and here. There are no differences between these Sensor Dots and Cradles compared to the ones that are included as part of your Byteflies Kit.
Sensor Dots and Cradles are not standalone medical devices. They can only be used as an accessory to a Byteflies Kit (Model 1). All the same safety precautions apply.