So far this year (2024) Houston we've had two storms that knocked down thousands of trees rendering streets blocked or worse. Anyone who has seen news from the path of Hurricane Helene has seen that the government either no longer can or no longer will offer any useful aid. You and your neighbors have to rescue each other, which often means chainsaws. However, chainsaw blades get dull with lots of use, like rescuing a neighborhood. Yes, you can stock up on a few extra blades, but it's unlikely that everyone with a chainsaw will be as prepared. That's where this shines! If you have a car battery with a charge, you can resharpen numerous blades, allowing the rescues to continue.It's easy to use, with guides for the most common blade angles and grinders for the usual blade thicknesses. That being said, this isn't a professional-level tool for foresters and lumberjacks. This is more of something stashed away for those "Oh damn!" times. I recommend spending another $9 and getting a bunch more of the grinder bits as these wear out after a few blades.This sharpener works on gasoline, gas-oil, or electric chainsaws. If you live somewhere with trees and natural disasters, this should be part of your emergency gear.