supply of improved high tensile tight lockimproved high tensile tight lock,improved high tensile tight lock center buffer coupler with aar h type head and balanced draft gear for fitment on bg passenger coaches confirming to rdso specification no. rdso/2011/cg-03 (rev-03) c onsisting of 06 items. (sr.1): tight lock coupler head aaa-h type with main pin qty-01 no. (sr.2) balance draft ge ar qty. 01 no. (sr.3)supporting device with fasteners qty. 1 no. (sr.4) manual uncoupling device qty. 01no. (sr. 5) base plate with fasteners qty. 01 no. and ( sr.6) support plate with fasteners qty. 01 nos [ warranty period: 84 months after the date of delivery ]