<p>BMK utilizes the latest technology in AGM, GEL, Flooded(Wet), Calium type deep cycle, VRLA maintenance free lead acid batteries charging.<br> Can be used with 12-100Ah batteries, while for the best results, use with 12-60Ah batteries.</p> <p><b>Four Stage Charger：</b><br> ※Stage 1:Desulfating the battery through 18V pulse, Charger enters this stage if it detects battery sulfation or severe discharger. Once battery is rejuvenated, charger moves to Bulk stage<b> (LEDs:1 ON,2-4 OFF ) </b><br> ※Stage 2: Bulk charge using charger highest rated current for the type of battery in use until it reaches 80% capacity. <b> (LEDs:1-4 Blinking Sequentially) </b><br> ※Stage 3:Absorption,the output voltage is limited to 14.7V while current declines as the battery charges to its full capacity without overheating <b> (LEDs:1-3 ON,4 Blinking) </b> <br> ※Stage 4:Float,At this stage, the battery is fully charged and the charger maintains the battery through pulse charging. <b> (LEDs:1-4 ON) </b></p> <p><b>How to use: </b><br> 1.Connect the AC cord to the socket, The [power] LED (red) will light on solid. <br> 2.Connect positive charger clip (red) to positive battery terminal, the black clip to negative, the “25%~100%” LEDs will light in sequence, <br>If the battery polity is reversed or output is shorted, all LEDs will flashing simultaneously, DISCONNECT&CHECK<br> 3.Depend on the charged capacity, 25%~100% LEDs will lights up solid, When all are ON, the battery is fully charged, you can disconnect the battery to use or keep it connected to charge in float mode. <br>If battery stays at stage 2 after 24 hours of charging, then the battery is defective. <br>