The "Blue and Improved" Original Line®  Z-Line cylinder feature permanent grease lubrication. Design enhancements have more than double the anticipated service life of this cylinder, designed for extremely tough applications.  This robust design features larger diameter, two piece piston rods that include a removable hardened rod stud. Bore Sizes:  3/4", 1-1/16", 1-1/2", 2"Larger diameter two piece piston rodsHeat treated alloy steel rod end studs are easily removed in case of failureStandard elastomer bumpers for quiet operationBlue and Improved design doubles previous cylinder lifePermanent grease lubricant requires no additional lubrication during serviceEngineering SpecificationsPressure Rating: 250 PSITemperature Range:Buna N seals: -20° F (29° C) to 200° F (90° C)Fluoroelastomer seals for high temperatures (up to 400°F) availableMagnetic piston option: max. operating temp. is 185° FMaterials:Rod: 303 stainless steelBody: 304 stainless steelEnd Caps: AluminumRod & Pivot Bushings: Sintered bronze