supply of material at various sites for sewerage works under zone 01 to 21 on rate contract basis , narmada sand , cement bag 50 kg , open bhatta brick , flag stone thickness 50mm , flag stone thickness 75mm , flag stone thickness 100mm , pvc pipe heavy duty 150 mm dia 6kg/ cm.sq. , pvc pipe heavy duty 200 mm dia 6kg/ cm.sq. , manhole cover with frame 600x450mm medium duty precast rcc manhole , manhole cover with frame 560mm dia medium duty precast rcc , manhole cover with frame heavy duty 450x900mm precast rcc , manhole cover with frame 560mm dia heavy duty precast rcc , manhole cover with frame 560mm dia extra heavy duty precast rcc , aggregate 20mm, 40mm