bids are invited for providing, fabricating and fixing of ac supply duct, return duct and plenum chambers with 22swg gi sheet for plenum chamber and 24swg gi sheet for supply and return duct , providing and fabricating the 25mm thick glass wool insulation work inside the supply duct and plenum chamber using 1mm aluminium perforated sheet and a tissue paper for locking the glasswool , providing and grouting of ms c channel on the parallel vertical walls of size 10ftx3inchx2inch with 5mm thickness for the fixing of the plenum chambers over the false ceiling at designated place , providing and fixing of 475mm x 475mm canvas of reputed make in between the plenum and machines 02nos, dampers of size 475mm x 475mm 02nos , providing, fabrication and fixing of powder coated aluminium grill, aluminium diffuser, aluminium volume control damper , providing, fabrication and fixing of powder coated aluminium return grill and providing, fabrication and fixing air control damper for supply duct total quantity : 313