The Uni-Flo2 is a soft, single sided cannula that works for any oxygen user at up to 6 lpm flow rates. Works fine with pulse does portable concentrators too!
The one-sided Uni-Flo2 is more comfortable and less bothersome to your nose. Some oxygen users have blockage or damage to a portion of their nose, or sores that make regular oxygen cannulas painful. The Uni-Flo2 is a great solution for those users. Come 3 to a pack.