(Excerpt from CLW manual for WAG7 locomotive)
IRAB-1 Brake system had been designed by Indian Railways for application in main line WAG-7 AC Electric Locomotives for hauling Graduated Release Automatic Air Braked train. The system comprises critical brake valves of WABCO design indigenously developed and supplied by RDSO approved sources i.e. M/s Stone Indian Ltd. and M/s SAB-WABCO India Ltd.
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