At first glance this appears to be "GMTX 7ZI", but that is because whoever was tasked with applying the roadnumber to this NW2 was not adept at making the curves needed to create a "2". GATX Rail Locomotive Group 721 was built in May 1949 as Elgin Joliet and Eastern 435, where it remained until at least August 1974. It was later sold to IEI Container Services, which retained that roadnumber (but I was unable to trackdown a reporting mark). It later "lost two-hundred" when it was sold to Rail Link, where it became RLIX 235. Eventually this switcher was sold to S&I Locomotive Services as SILX 235. On February 20, 2013, this locomotive was sold to GATX Rail Locomotive Group, which gave it yet another identity, GMTX 721, in November 2014. 68 years after it was built, it was photographed working GATX's Colton Repair Facility, although it had been here for a few years at this point (it was in service here as far back as January 2015, if not late 2014, and was still here in April 2019). In June 2019 this locomotive was seen in transit at Birmingham, Alabama, but no destintation has turned up in my research. As of February 2021, this locomotive was no longer registered in UMLER® (Railinc's Universal Machine Language Equipment Register, an equipment registry for the railroad industry) and is presumed scrapped. (Colton, California – July 5, 2017)
