Tender For supply of 0 to 500 mmwc range differential pressure transmitter as per attached specification , digital differential pressure controller as per attached specification , magnehelicgauge as per attached specification , photohelic gauge as per attached specification , 1 by 8 inch nptm x 1 by 4 inch od ss 304 straight connector with nut and ferrule , 1 by 8 inch nptm x 1 by 4 inch od ss elbow connector with nut and ferrule , 1 by 4 inch nptm x 1 by 4 inch od ss straight connector with nut and ferrule