7' Tubing & Mouthpiece - Each This Neb Kit is Disposable it would need to be replaced every two to three weeks. * The timeframes do depend on the frequency of usage. * If you're noticing that the medication isn't nebulizing as quickly or as much  it's time to replace the neb kit. Kink-resistant tubing * Anti-spill T design * Leak-proof and secure seal with simple 1/4 turn assembly design * Very low dead volume (07cc) * High medication bowl capacity (13cc) * Graduated volume (cc) markings on bowl* Latex Free *