This Connector allows you to port in Oxygen into your CPAP therapy. This adapter connects directly in line with your CPAP Tubing. It can be connected between the Mask and the CPAP tubing or connected between the CPAP Tubing and the CPAP Machine itself. If you have heated tubing the connector must be placed at the connection point between the mask and the CPAP tubing. Once connected you simply connect the Oxygen tubing to the small nipple on the adapter.