Ventis AC01350 is a 6" x 25' Insulated Flex Pipe used on the HE250R, HE275CF, HE325, and ME300

During operation, the fireplace requires fresh air for combustion and draws air out of the house. It may starve other fuel burning appliances such as gas or oil furnaces. As well, exhaust fans may compete for air, causing negative pressure in the house, resulting in smoke entering the house from the fireplace. This situation is aggravated in modern airtight houses. To overcome this problem, we strongly recommend that you bring fresh air to the fireplace.

To complete the fresh air installation, you will need a 4" insulated flexible pipe. Use the length required for your installation while respecting the maximum length of 30 ft (9 m). To avoid condensation, it is recommended to use an insulated pipe long enough and containing a "P-Trap" loop. This configuration can be found inside the chase but must at all times maintain clearances to combustibles. 

This insulated pipe complies with HVAC type, ULC S110 and/or UL 181, Class 0 or Class 1

Carcinogens: This product can expose you to chemicals including Lead, which is [are] known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.