corrigendum : supply of high tensile aar-h type tight lock coupler with transition screw coupling for fitment on b g passenger coaches of indian railways and balanced draft gear, un-coupling devices, supporting devi ce and other related components as per spec no rdso/2009/cg-22 rev-01. [ warranty period: 84 m onths after the date of delivery ] [quantity tolerance (+/-): 5 %age , item category : normal , total po value variation permitted: max 8 lacs ] ] mech stores depot-ubl, swr