Profile: Precision Relays Ltd. designs and manufactures relays for the utility, defense and process industries. We provide instantaneous, special function, latching & time delay and dual coil relays. We also offer series 12 relays, which are general purpose 2 or 3 pole changeover relays for AC or DC operation. Our Series 339 relays are magnetic cut-out or overload trips are designed for the protection of AC or DC circuits. They can be supplied for either voltage or current operation and may be used as a manual re-set relay. An enclosed plastic cover version can be supplied if required.