Adwords conversion tracking code.
https://support.google.com/adwords/answer/6095821#get_tag
Analytics and Tracking · Advertiser Tracking
Get access to data on 1,010,358 websites that are Google AdWords Conversion Customers. We know of 662,168 live websites using Google AdWords Conversion and an additional 348,190 sites that used Google AdWords Conversion historically and 337,228 websites in the United States.
Get a list of 1,010,358 websites using Google AdWords Conversion which includes location information, hosting data, contact details, 662,168 currently live websites and an additional 1,619,134 domains that redirect to sites in this list. 348,190 sites that used this technology previously and 337,228 websites in the United States currently using Google AdWords Conversion.