Mini Multitube Once-through Boiler GX-S (Gas fired)GX-40, 60, 90, 120,160, 250, 350 (Equivalent output 40 - 350 kg/h)Main Features- Quiet operation due to special noise-absorbing body and low-noise combustion burner- Slim and easy to run because the operations are concentrated in the front- Boiler efficiency 87%