1.5V Rechargeable D Size Lithium Batteries 8 Pack with USB-C 4-in-1 Charger - Long Lasting Power for Flashlights, Toys, Floodlights & Emergency Kits - Perfect for Camping, Home Use & Outdoor Adventures

I moved into a beautiful home a year ago and was shocked that the bathroom didn't have an exhaust fan. I quickly learned that you really need to vent the bathroom to avoid mildew after a shower. I picked up a 10" battery powered fan that I stick in the window while I shower. It takes 6 D batteries and I could get about 6 weeks out of copper top premium batteries so it was not cost effective.The first thing I liked was the fact that I have USB - C chargers everywhere and this set came with a dongle that will charge 4 batteries off of one USB port. Nice and convenient. The second thing was that the fan actually runs stronger on these and so far they're past 6 weeks with no slow down.I'm now going to replace my other size batteries with these as needed.