Tender For supply of water immersion heater 4kw 230/440 volts, flange 2'' bspp depth of immersi on 260mm as per is: 4159 of 2002 (reafirmed year 2017 ) with amendment no. 1&2 (with isi mark) mineral filled sheathed heating element [ warranty period: 30 months after the date of d elivery ]