Fisher & Paykel has developed a line of high-performance circuits that has a patented spiral wire circuit technology that is unique to the industry. This technology allows for more consistent temperature delivery throughout the circuit, helping to maintain a virtually condensate-free environment and improvement for optimal humidification. For flows more than 4 liters/min. Length is 4ft . Includes pressure port, 1/8in pressure lines and water trap. Use with # 11 Ventilator (KEY BELOW) Note: All single-heated limb circuits can be connected to either a 900MR901 or 900MR900 heated wire adapter for MR730 humidifiers and a 900MR801 or 900MR800 heated wire adapter for MR850 humidifiers. (( KEY: #1: Bear 1®, 2®, 3®, Puritan Bennett® brand MA-1™, MA-2™. #2: Bear 1000®, Bear 5®. #3: Bird 6400® #4: Bird 8400®, T-Bird®/Legacy #5: Draeger Evita™ #6: Hamilton Veolar® #7: Infrasonics Adult Star™ #8: Newport Breeze®, Newport Wave® #9: Nellcor Puritan Bennett® 7200, 840 #10: Nellcor Puritan Bennett® 740, 760 #11: Siemens® 300/900C.))