occurred between classes 121, 141 and 181. All but three (B121, B125, and B135) were fitted with Train Door Control equipment for operation with the Inchicore-built, British Rail Mark 3 based, push-pull train units. The push-pull equipment of locomotive B132 was subsequently decommissioned. Entering service in 1989, these trains, consisting of a single 121 Class and up to six carriages, were mainly used on the Dublin northern suburban passenger railway service. These were to be the last regular passenger duties for the 121s within Greater Dublin. The Limerick shuttle continued to be worked by 121s for several years after this date. In 1994, a railcar revolution had begun, and the push pull carriages were later re-deployed to inter-city duties with the 201 Class locomotives. Withdrawal The first member of the class to be withdrawn was 125 in 1986 following an electrical fire, though it had been extensively damaged in an accident twelve years previously. However it was not scrapped until 2002. By 1995, the class 201 had replaced the class 121 on most passenger routes. Throughout the late 1990s the fleet dwindled, and by 2005 only numbers 124 and B134 remained in service, with number 123 in storage for five years until eventually being scrapped in 2008. The rest of the fleet was also scrapped, due to the decline in freight traffic that they were also used for. Their last official scheduled mainline passenger working was on 9 July 2005 on the Sligo line. The last known passenger working of this class was the 13:15 Waterford-Heuston service on 18 January 2007. Previously, these locomotives had filled in on the Manulla-Ballina service or the occasional service from Limerick. The last use of them in public service was in the early months of 2008 on maintenance trains. By this stage 124 and 134 were the only survivors. Both were retired by degrees and officially withdrawn in July 2008, though at this stage neither had done much for many weeks. Preservation The Irish Traction Group has preserved locomotive 124. It is located at Moyasta Junction on the preserved West Clare Railway. The other surviving member of the class, locomotive B134, is owned by the Railway Preservation Society of Ireland (RPSI), and is undergoing restoration. On 19 July 2016 it was hauled by 071 Class locomotive 071 from Inchicore to the RPSI's locomotive shed at Dublin Connolly. Later that year it was returned to