Wall thickness complies with ASME B16.34 Class 1500#,Strain Hardened Stainless Steel Stem,Memory Seal Seats Compensate automatically for wear and fluctuations of pressure and temperature,Blow Out Proof Stem,Solid cup and cone type PTFE Stem Seal- Adjustable,Stem bearing in Gland nut reduces Side thrust effect,Live-loaded thrust washer prevents galling and provides a secondary stem seal,RPTFE stem washer prevents galling, reduces torque and provides secondary seal