Dogtra e-collars are known for their patented Rheostat intensity dial, but with the EDGE you can now switch to the included traditional €œselector dial. Whether you prefer a smooth stimulation or a selector style with €, the EDGE was made for you. nEach receiver/collar comes equipped with multiple colors for the High Intensity LED Location Light. The location lights help to find and distinguish dogs easily in low light/dark conditions. Fully expandable up to 4 dogs The buttons on the front of the transmitter enables control of up to 4 receivers/collars. To add an extra collar it is as easy as touching the extra receiver to the transmitter and telling it to sync. nThe 2-hour rapid charge Lithium Polymer batteries are housed in a separate compartment on the transmitter/receiver for easy replacement. Dogtra has given the EDGE a warranty that is a full year longer than any competitors remote trainer. Dogtra Company provides the original purchaser with a 2-YEAR WARRANTY. The warranty begins from the date of purchase. For the first two years, coverage is for parts, labor, and accessories. System includes one transmitter, one receiver collar, a battery charger and splitter cable, a Test light, an owner's manual, an exchangeable selector dial, two contact point extensions with an adjustment tool, a metal belt clip with two screws and a carrying case. Features n Rheostat/volume style with stimulation levels 1 127n Selector/step style with stimulation levels 1 8n 1 mile rangen Nick/Constant/non-stimulating Pager vibration modesn Location light with 4 selectable colors white, red, blue and green