Features: 350 cc Water Capacity and easy-to-turn 3 wings butterfly nut Very safe sealing to the Oxygen source Audible 6 psi over pressure alarm whistle Transparent MINIMUM-MAXIMUM water level strip indicators Multi pointed diffusion ports for a positive humidification Concave design lid to avoid rain drops inside the bottle Operational Information: It is very well known fact that Oxygen has a drying effect at the airways when inhaled at high concentrations especially. Thats why, when it is used for Oxygen Therapy for long term, it must be humidified for avoiding the dryness effect which possibly may cause problems. The easiest and most economic way for this; is making the Oxygen pass through the clean water. Until the Oxygen gas leaves the water, it gets humidified and becomes suitable for the patient use. And in case of an obstraction occurs on the way till the patient, the bottle inner pressure increases and when it reaches to 6 psi level, there is an audio alarm whistle which warns the user that there is something going wrong on the line and there is no Oxygen delivery made at that moment. The lid seals safely without any gasket or etc. requirement at a half way turn only. It can be used with all Oxygen Sources like Wall Outlets, Gas Tanks, Liquid and Concentrator systems safely.