The power cord cable supplied by the Celestron Power Tank 17 from OPT did not fit the into to Power Tank 17. I had to use the power plug suppled form Celestron with my 925 Celestron scope.
Works far better than expected, highly recommend this product purchased from OPT.
I've had this battery for eight years now with no problems. It does run down when not in use but I've had no problems with recharging even after months of storage (at room temperature). The battery is not meant to be left plugged in when not in use (as described by another reviewer). According the manual it is dangerous to do so. The battery will last much longer by following the tips in the manual. But it does sound like Celestron's quality control is inconsistent at best.
I have now owned the Celestron 12V 17AH power tank for 2.5 years. During the 2.5 years I have kept it plugged into the wall charger whenever it is not in use. It has never failed me during observing and easily powers my Edge HD 11" /CGEM DX and either my Dew Removers or my camera. The main LED spotlight is very bright and the red light is very useful. The radio does not work very well as there is no antenna. I have used it to jump start my car so this function may be helpful if your car battery dies. At 2.5 years the battery did start to fail but this was expected. I was able to easily replace the battery for about $45.
After a month the unit failed to recharge. I opened the case and found the soldering job on the circuit board was so sloppy that beads of solder were shorting out the circuit. After scraping away some of the excess solder the unit recharged and was usable for a few months more. But now something else has shorted out and the unit is now a door stop. During the few months the unit mostly worked it was not a joy to use. There are far, far too many gadgets on what should be simply a battery with a charger, and unfortunately absolutely none of the gadgets work better than very poorly.
I did buy this from this from another store but I bought my telescope here. Tried it once and it would not take another charge. I'm new to this activity but when I waste a hundred forty five dollars, including shipping, I do get upset. My next attempt will be to use a 110 Ah Gel Cell connected to a Solor charger.