Profile: Vaporless Mfg., Inc. is a manufacturer of mechanical line leak detectors and electronic line leak detection from the forecourt of service stations & truck stops to boat docks, loading racks, day tanks & airport fueling systems. Our product line includes leak detectors, overfill protection valves, leak detector and sump testing equipment. Our 99 LD-2000 is the mechanical leak detector capable of holding the line pressure after the pump is off even with the pump component wear or failure. Our LDT-890\AF is designed for "Bio" fuels. While typical blends of ethanol and methanol through 20% concentration are fine for the standard LDT-890, higher concentrations and biodiesel blends above 5% will shorten the service life of the standard LDT-890. The LDT-890\AF is recommended for ethanol & methanol blends above 20% and biodiesel blends above 5%. Our PLC-5000 system consists of two primary components, a central control node (CCN) and a leak detector node (LDN). The PLC-5011 CCN and PLC-5012 CCN utilize LonWorks power-line transceivers, communicating with their LDN over existing electrical wires powering the submersible. The PLC-5011 CCN is designed to provide for operation of control valves such as those used in the transition sumps of marinas, between the underground portion of the line and the exposed dock line. This eliminates thermal effects on the underground portion of the fuel line.