There are 40 locomotives of this class, all designed and manufactured by American company Progress Rail's Electro-Motive Diesel subsidiary.

Class 6600 locomotives are used on both freight and passenger trains.

Those are the strongest and most advanced broad-gauge locomotives in the Bangladesh Railway.

[1][2][3] In 2019, Bangladesh Railway ordered broad-gauge diesel-electric locomotives from American manufacturer Electro-Motive Diesel for ৳ 1,123.5 crore.

These are equipped with the EM2000 microprocessor control and AC traction motors.