3/8" Brass Polybutylene Barb x 3/8" Brass, Lead Free, Pex Coupling, Makes A Transition From Polybutylene Tubing To Pex Tubing & Connected With Stainless Steel Cinch Clamps & Cinch Tool TV #608-743, ASTM F-876, ASTM F-877 To SDR-9 Dimensional Standards, NSF 14 & 61 For Use In Potable Water Systems, CSA B137.5 Standards, NSF CL-R Certified For Use In Hot Water Systems Where Chlorinated 140 Degrees Fahrenheit Hot Water Can Be Constantly Re-Circulated, The Wetted Surface Of This Product Contacted By Consumable Water Contains Less Than 1/4 Of 1 Percent, 0.25%, Of Lead By Weight, Meets AB1953 California & VT S152 Vermont Low Lead Restrictions.