1.Flexible shaft reaches tight areas.2.Non-conductive coating will not zap expensive computer circitry3.ultra sensitive mic&lifier give full range of sounds needed by the professional4.Limited distortion or unwanted sounds.5.Quickly pinpoints noise and location of bad bearings bushings,dirty fuel injectors,wind&air leaks,noisy valves & lifters.6.7-Sound level control settings 60db to 120db7.db meter-monitor8.A-B tone control setting9. high-low volume control10.battery check position on control switch11.includes 9 volt battery.12.inductive metal probe included