very handy when it works! the first I received began to make very shrill squeaks after 3 uses the second ran for 20 minutes and then stopped by emitting tones and 4 beeps every 30 seconds indicating a problem on me chargeur.Comme the request, I removed the battery for 5 hours and then returned to service and I still have the same problème.Heureusement I did purchase from amazon that has a sav excellent and very efficient and performs exchanges 2-3 days.