Mechanics stethoscope made of heavy-duty vinyl tubing and ABS plastic ends. Strength.,2 Pack / packing. This engine stethoscope set includes 2 metal probes: 3.5 inch and 8.5 inch,extending to 12” long,easily access in hard to reach spaces.,Mechanics Auto Stethoscope has a super sensitive noise diagnosing probe with comfortable earbuds for locating troubles within the engine block, easily detecting the problems.,Suitable for identify broken gaskets, bad pulleys, damaged gears, defective valves, water pump failures, and other defective or damaged parts that cause odd noises and faulty operation.,If you have any questions, please contact us timely and we will give you a satisfied solution.