Supply of Cut Off Angle Cock With Vent Complete Cut Off Angle Cock With Vent Complete For Air Brake Wagons To Rdso S Drg. No. Wd-88123/S-01, Alt. No. 2Two Or Latest And Rdso S Drg. No. Wd-88123/S-02, Alt. No. 6Six Or Latest. To Rdso Specn. No. 02-Abr-02 With Amendment No. 4 Of June 10 Or Latest. This Item Is Reserved For Procurement From Rdso Approved Sources Only..