If your car came with the non-smoker center console cup, you can replace it with the smokers version with closing lid. This adds a lighter and console 12 volt socket (see the related item below). So by adding the ashtray and this harness, you will have a complete "smokers package" with ashtray.
Can be used on all 2013-2016 Boxster, Cayman, and 911 Carrera models. Adding electric isn't possible for all models.