These Wagons are also known as Rapid Discharge Coal Hopper Wagons. The type used by Railways is BOBRN type having 8 underside doors and the one used by Thermal Power Stations has 12 underside doors.

These Wagons can carry 60 tonnes graded coal and can ply in merry-go-round system. The loading is done from the top and unloading is done automatically from the bottom through Pneumatic Door Operating Mechanism activated by Rail Side Devices mounted on the track. The electro-pneumatic system is actuated from 24 to 32 Volt DC operated Line Side Equipment at the desired place. The Door Operating Mechanism has been successfully developed and are in wide use. The wagons have the same features as other 8 wheeler bogie type wagons used for carrying bulk load.

Product > Specification V	Open Coal Hopper Wagon (BOBR)	Open Ballast Hopper Wagon (BOBS)
Track Gauge	1676 mm	1676 mm
Total Weight	81.28 M.T.	91.6 M.T.
Tare Weight	27.45 M.T.	30.4 M.T.
Load Capacity	58.38 M.T.	61.2 M.T.
Volume Capacity	57.20 cu.m	34 cu.m
Overall Length	11600 mm	11597 mm
Width of Carbody	3500 mm	3020 mm
Height of Carbody	3735 mm	3304 mm
Coupler Type	A.A.R 'E" Type (High Tensile) with high capacity Draft-gear	A.A.R 'E" Type (High Tensile) with high capacity Draft-gear
Bogie Type	Casnub 22 NLB Cast Steel	Casnub 22 NLB Cast Steel
Brake System	Air & Hand Brake	Air & Hand Brake
Max. Speed	100 Km/h	100 Km/h