Supply59 CSST Fittings must be installed strictly by a licensed and qualified gas technician who holds a valid gas certification recognized by the local regulatory authority and has successfully completed the Supply59 certification training. 1/2″ CSST Adapter Brass Spare Ring Certifications and Listings: CSA Certified, CSA Listed Operating Temperature Range: -20 to 150 degree Maximum working pressure (psi): 25 Manufacturer Warranty: 5 years Fitting Material: Brass