[LONGER LENGTH IMPROVES CONVENIENCE]: The length of this short tube is longer than the original tube, and the diameter size remains the same, allowing you to maintain flexibility and comfort during sleep. [TWO ROTATABLE PARTS INCREASE FLEXIBILITY]: The Short Tube has been designed and improved to increase two rotation positions, which relatively strengthens the flexibility of the short tube, and effectively reduces the twisting and knotting. [DURABLE QUICK-RELEASE BUTTON(CLIPS)]: The quick-release button is made of durable material, easy to install, and has enough tension to prevent it from falling off. [AVOID LEAKAGE AND Reduce NOISE]: The improved short tube has better fitting connection around the elbow to effectively avoid leakage, so that there is no noise to give you a quiet sleep. [PACKAGE CONTENTS]: These are the improved replacement tube assembly for N20, includes the elbow, short tube, and swivel.