These needles are the correct size, and will not puncture the liners if properly used WARNING: Item cannot be returned or exchanged if liner is weakened or punctured as a consequence of poor inflation or needle use A flexible liner created for many head styles delivers consolation and stability Detachable https://speedflex-adult-large04825.techionblog.com/30995346/5-simple-statements-about-adult-medium-speedflex-explained