Instructions followed. Charged both batteries directly from the case. I waited for the green light on the charger to come on and everything was ready. Filled as instructed, the lube flowed smoothly at both high and low speeds. This gun is amazing. Run it through about 50 grease fittings with no problems. Lincoln is my favorite butter dish. When I was at Caterpillar I had an old 18 volt Nicad Lincoln grease gun that worked great day in and day out without missing a beat. I must have gone through thousands of oilers and never let myself down so I decided to buy a Lincoln again at my new job. Weight wise I have always worked with heavy equipment and exercised regularly so it is not difficult for me at all and makes my life easier and easier.