Taco T571-2 3/4-Inch Gold Series Zone Valve Taco, 2- 3/4 inches Sweat Zone Valve Gold Series, For Hydronic Heating Applications, Quiet & Dependable Operation, Manual Open Lever & Twist Off Head Makes Installation & Service Easy 0.75-Inch sweat Two way zone valve Normal Flow Ranges (GPM)-1 - 4.5 Max. Fluid Temp-240-Degree Min. Fluid Temp-40-Degree