These needles are the correct length, and should not puncture the liners if appropriately used WARNING: Merchandise cannot be returned or exchanged if liner is weakened or punctured because of improper inflation or needle use A flexible liner designed for many head styles provides comfort and balance Detachable humidity-resistant liner https://riddell-speedflex-adult-l64905.digitollblog.com/30766345/the-basic-principles-of-adult-medium-speedflex