Tender For supply of set of standard calibration gas canister for dga consisting of (1) methane, ethane, ethylene, acetylene, hydrogen, co & co2 each 100 ppm and nitrogen balance, qty- 01 no. (2) methane, ethane, ethylene, acetylene, hydrogen, co & co2 each 500 ppm and nitrogen balance, qty- 01 no. (3) methane, ethane, ethylene, acetylene, hydrogen each 1000 ppm, co & co2 each 5000 ppm and nitrogen balance qty- 01 no. with pressure gauge, septum and knob arrangement to draw sample directly from canister using gc syringe. preparation tolerance plus (or) minus20 percentage & shelf life 12 months. canister capacity 0.5 litres, filling pressure 20 kg/sq.cm with test certificate and suitable septum as spares.