It was introduced after World War II for passenger duties, marking the change from 'X' to 'W' as the classification code for broad gauge locomotives.

WP class locomotives were capable of going up to 110 km/h (68 mph) and were easily recognized by their bulging, cone-shaped nose, usually with a silver star device painted on it.

Among them, one constructed by Baldwin, number 7200, in 1947 and another by Fablok in 1959 are a part of the collection of the National Rail Museum, New Delhi.

[5] WP7200 received a full heavy overhaul at Amritsar works in April 2015 and is now kept at Rewari shed near New Delhi for excursion service.

7015 built by Fabryka Lokomotyw or Charznow Poland is another Polish preserved WP engine and has been restored to full mainline running order and runs mainline heritage excursion special trains, being preserved at Rewari shed, 7161 is another locomotive built by Chittaranjan which has been fully restored to full working order on mainline excursions, being preserved at Siliguri.