Remote battery watering system lets you fill all batteries to proper electrolyte levels from a single fill tube, using a simple hand pump. Safer and more accurate than conventional filling. Installs in minutes without tools. Sends water only to low cells without overfilling! Works with any distilled water container. Fits all 12V flooded lead acid batteries in group sizes 24 through 31 with standard 3-cell and spacing of 1-5/8" center-to-center. Same great features as the Qwik-Fill„¢ double battery watering system (558754), but for one battery. Used as an add-on to the double kit. When used for single battery filling it requires squeeze bulb filler (558753), sold separately. Priced each.