Western Enterprises Oxygen Flow Gauge Regulators Chrome-plated brass body with all brass high-pressure chamber. Internal reseating relief valve protects against over-pressurization. Sintered filter for additional safety and to extend regulator life. Single-Stage, Pediatric Single-Stage, and Two-Stage models available. Pack of 1 WARNING: This product can expose you to Lead, a chemical known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov - Lead