There are 4 common EM power units used since 2010. Below is a breakdown of when they were used and what is included with each. For a breakdown of the power unit click the part number and we'll take you to a full breakdown.
70430570 is a power unit with thermal switch. This was standard from 3/2012 to 5/2013; optional between 5/2013 and 1/2016; and standard again after 1/2016.
70430575 - EM-25 and EM-3 power unit, without a thermal switch; standard between 5/2013 and 1/2016.
70430550 - EM-25 and EM-3 power unit; standard prior to 3/2012