Pressure Systems International has improved its patented Through-Tee to include a corrosion resistant stainless steel retaining ring. The Meritor Tire Inflation System by PSI™ has improved features which address many environmental and safety issues facing truck fleets, including the devastating affects of corrosion on fleet equipment. In addition, a larger longer lasting stainless steel tube in the latest Through-Tee design allows for higher air flow to the tire.