The numbers 111 to 400 formed the largest series of 2-4-2 express locomotives used by the PLM. The 290 locomotives were built between 1879 and 1883, most by the PLM's own shops at Paris and Oullins. 40 had come from Sharp, Stewart & Co. of England. The wheel base was made as short as possible and both the leading and trailing axle had 20 mm of side play. The boiler was very long, had a Belpaire firebox and was originally operated with ten bars. Later the pressure was increased to eleven bars and some received a radially adjustable leading axle. They were later equipped with air brakes, as could be been from the air tanks above the firebox in the photo.

As it was found out that these locomotives were hard on the tracks, the PLM started to rebuild them early on. Between 1890 and 1897, 97 were rebuilt to the 4-4-0 wheel arrangement. To decrease the length of the boiler without sacrificing power, they installed finned Serve tubes of greater diameter. They also got a wind cutter cab and now had better running characteristics. Although even the original 2-4-2 variant was officially approved for 120 km/h, the rebuilt 4-4-0 locomotives could regularly be operated at these speeds. Some were operated until the last years of the thirties and received SNCF numbers.

Between 1913 and 1918, 60 more were rebuilt to 2-6-0. As the first series of rebuilds had been very costly, this one had to be cheaper. So their boilers were taken over virtually unchanged, but now operated at 14 bars. The last rebuilds were into 0-8-0T tank locomotives. Firstly, 50 were rebuilt by the PLM shops at Paris and Oullins, and by the company of Decauville and numbered 7701 to 7750. The company of Creusot rebuilt 84 more in 1924 and 1925 which were numbered 7751 to 7834. Although both batches were virtually identical, the first one was later designated 4 AM, while the second one became 4 BM.