Size: 2â-12â Pressure Rating: 150-300 LB Material: Cast iron, Carbon Steel, Stainless Steel End: BW, RF, RTJ Operation: Manual, Pneumatic, Electric Design & Manufacture Standard: ASME 16.34, DIN 3352 Face to Face: ASME B16.10, DIN 3202 End Connection: ASME B16.5, DIN 2543-2545 Test Standard: API598, DIN 3230 Bolted bonnet OS&Y Double seal design(bellows+packing) Multiply bellow with long service life Effective for energy savings