Teleflex Hydraulic Cyl O B Front MountTele Hyd Cyl. O B Front Mount Updated cylinders fit the same applications as the prior models. Improvements over previous models include: Updated styling, a more robust barrel, new sealing systems and materials with excellent resistance to compression set, and new adjustable stainless steel O ring fittings (ORB). Front Mount cylinders are balanced and the most commonly used. Recommendations: Single Engines: Single Cylinder: 350 HP Max, 65 MPH Max