This is my second Shark Freestyle wireless navigator because they're great for a quick everyday cleaning, but in about a year they die - a dead battery. I ordered this replacement battery - delivered on time - easy to install - and now my Shark Wireless Freestyle is like NEW! Great performance and suction power again! I don't know how long the spare battery will last as I only have a couple of weeks. If these batteries will do, then this is the way!