Fleetguard® SK15959. This sensor monitors restriction across the air filter. The LED indicator changes color from green to yellow and then to red based on the restriction level and provides both a visual indication and electrical signal of filter status. The inbuilt logic waits for 5 seconds of restriction state before latching, preventing false alerts. SK15959 can be a part of the FleetguardFIT™ system. FleetguardFIT™, which stands for Filtration Intelligence Technology, the most comprehensive filtration monitoring system.