JET INDUSTRIAL DUTY 12.5 AND 22.5 TON HYDRAULIC JACKS To assure dependability of these industrial strength hydraulic jacks, they have been tested at 150% of their rated capacity. These jacks are unaffected by temperature extremes and rigidly adhere to ANSI and JIS standards. They feature an electrically welded base and cylinders to assure strength and eliminate leaks. Common release valve assemblies and other interchangeable parts, for quick repair, are standard.