supply of overhead double-acting concealed door closer mechanism as per item no. 18 of rcf d rg. no. mi006232 alt 'd' for swing door entrance to ac area in lhb ac coaches. [ warranty period: 30 months after the date of delivery ] [quantity tolerance (+/-): 5 %age , item category : normal , total po value variation permitt ed: max 8 lacs ] ] - overhead double-acting concealed door closer mechanism as per item no. 18 of rcf drg. no. mi006232 alt 'd' for swing door entrance to ac area in lhb ac