FURminator Dog Nail Grinder Includes Replacement Grinder The light turns on during use. This is a FURminator product, so you can use it with confidence. Operation has been confirmed. There is a slight gap in the part where the batteries are inserted and closed from the time of purchase. It fits snugly and does not come off during use. Since it is an overseas product, it may have been this way from the beginning. There are some fine cracks in the transparent cover at the tip, but it works fine at both low and high speeds. It has been stored without being used. The packaging has been discarded. Everything in the photos is included.