Profile: Hydraulic System Products Ltd. is a provider of hydraulic systems. We serve various industrial sectors. Our test point plugs are installed in hydraulic systems at strategic points to provide easy access for our Hydra-test probes. This plugs may be installed temporarily during commissioning and fault finding or left permanently installed to assist in routine servicing and maintenance. Our multi-function testers measure flow factors using in-line mounted, bi-directional turbine blocks, pressure factor using test point plugs and transducers, temperature factor using thermistors or thermometers and speed factor using plug-in electro mechanical or photo tachometers. Pilot operated check valves we present with is a spring seated poppet valve that allows free flow in one direction, the application of pilot pressure allows reverse flow. In case of our double pilot check valves flow is locked in both directions until one of two pilot ports is pressurised to permit flow in the required direction.