Pulsar PSR Billet Transition Flange T4 Open to 2.5" SCH-10/40 Piping (Hardware Kit Included) - 164300402 - Item Details: Excellent billet transitional flange, machined from 304 stainless steel block for a smooth flow and perfect sealing surface By simply inserting your tubing into the port, you can easily weld them together, no extra fabrication needed Hardware Kit included for a easy installation 5 Options are available： SKU: 164300301 - T3 open flange for 2″ O. D. Tubing (DOESN’T FIT 2″ NPS PIPING) SKU: 164300401 - T4 open flange for 2″ SCH-10/40 Piping (2.375″ O. D.) SKU: 164300402 - T4 open flange for 2.5″ SCH-10/40 Piping (2.875″ O. D.) SKU: 164300601 - T6 open flange for 2.5″ O. D. Tubing (DOESN’T FIT 2.5″ NPS PIPING) SKU: 164300602 - T6 open flange for 3″ O. D. Tubing (DOESN’T FIT 3″ NPS PIPING)