My batteries are hard to get to, even with a turkey baster. Found this at FishUSA, Looked like it would work better than anything I had seen. I have less than $45 invested, and figure I saved more than that today. Cranking battery was the lowest, esp on the positive side. Hose connected to a water bottle from WM did the trick. I threaded the water spout and screwed in a hose connector. Turn it on at the bottle, insert the battery filler In a cell, press the thumb valve, fill until the ‘eye’ turns black. It’s full. Some cells I couldn’t see the eye, so it was fill and check until it was full. Easy enough. Thing about it, I was able to reach all the cells with this.