The new Rapid RH® L6 Smart Sensors are not compatible with previous readers (i.e., the Smart Reader and the Easy Reader). We’ve designed the new Total Reader® to have stronger, more ruggedized pins (in addition to other features), necessitating a change in the compatibility. To make this transition as easy as possible for our customers, the Starter Kit+ and WFP400+ Professional Kit come with a Total Reader. We also offer a 5 pack of Smart Sensors that includes a Total Reader.