The hole punch cylinder features permanent grease lubrication. Design enhancements have more than doubled the anticipated service life of this cylinder, designed with a 1" stroke and includes a steel cutter available in 7 different diameters. These cylinders are designed to punch millions of holes in thin poly material (3 mil thickness or less).Bore sizes:  3/4"Cutter diameters:  1/4", 5/16”, 3/8”, 7/16”, 1/2", 9/16”, 5/8”Can be ordered with cutter omitted, allowing customers to add their own cutter designHollow rod design creates an air jet to eject the cut-out slug every cycleNEW!  Blue and Improved design doubles previous cylinder lifeNEW!  Permanent 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) availableMaterials:Rod: Ground and polished carbon steelBody: 304 stainless steelRod Guide: Nickel plated steelRear Head: Aluminum