These needles are the correct size, and will not puncture the liners if correctly applied WARNING: Solution can not be returned or exchanged if liner is damaged or punctured resulting from poor inflation or needle use A flexible liner created for many head shapes gives comfort and ease and security https://speedflexadultlarge46891.mybjjblog.com/the-single-best-strategy-to-use-for-adult-medium-speedflex-43967034