supply of set of purg-o-mat automatic float air vent valveset of purg-o-mat automatic float air vent valve, set of purg-o-mat automatic float air vent valve for overhead roof wate r tank and vaccum valve consisting of following items. (1) purg-o-mat automatic float air vent valve with shut off valve having thread bsp 3/8 to rcf drg. no. lw 63150, item no. 4 alt e qty-01 nos. (2) vaccum valve g-1/2 to rcf drg. no. lw 63150, item no. 3, alt e qty-02 nos.. [ 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 ] ]