Screwed hat Oscillation type disc Damper & Counter weight for options Interior pin reduces leaks ONE EYEBOLT: For 150Lb-8",300Lb-8",600Lb-6",900Lb/1500Lb/2500Lb-4" and more. B BOLTED COVER: Standard bolted cover or welded cover for option. C END CONNECTION: flange (RF, RTJ) or Butt-weld D BONNET-COVER SEAL: Male and female joints or tongue and groove joints or ring joint. E EXTERIOR LEVER AND WEIGHT: inside the hinge discover the leaks. For external hinge pin swing check valves, external lever and counterweight are available. F SEAT RING: Separate heavy duty complete ported rings for easy maintenance. Screwed or welded connection to the body. H BODY-BONNET JOINT: Flat face gasket joint for 150 lb. valves; male and female joint for 300lb & 600lb; Ring joint for 900lb and higher.