Exhaust Muffler, Air Inlet Size 1/4 in, Air Inlet Type NPT, Hex Size 9/16 in, Filter Element Material Sintered Bronze, Maximum Operating Pressure 300 psi, Maximum Operating Temperature 300 Degrees F, Fitting Material Nickel Plated Steel WARNING: This product can expose you to chemicals including Nickel (Metallic), which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov. -