supply of set of valves [ leveling valve qty. 02 nos. and duplex check valve qty. 1 no. ] to ftrtil leveling valve part no. 038001000, duplex check valve part no. 039001500 or kbil leveling valve part no. ii68831, duplex check valve part no. 1.3.1902 or m / s escorts leveling valve drg. no. 3eb6631 alt 03, duplex check valve drg. no. 3eb6632 alt.03 [ one set consisting of 02 items and 3 nos. ] . material to be procured from rdso approved vender for air suspension control equipments conforming to rdso spec. no. c-k 407 ( rev.03 ) amendment-1 of september 2018. [ warranty period: 30 months after the date of delivery ]