This is a must have tool,to be used in conjunction with nitrogen under pressure. It will not find a low pressure leak as well as some of the other tools, but in a noisy,dirty environment, it is very well suited to its job.

I'm a senior technician and have several H10 and a couple hand held sniffers. Have found this tool very useful. It locates leaks by way of sound rather than sniffing refrigerant. I can quickly search system under pressure with nitrogen or refrigerant. i can leak search a system that has been flat by adding just nitrogen. i can leak search a system and hear the leak through the armaflex insulation. Havent had an application to find a leak inside a wall cavity but i'm resonable sure it will hear it.. And, it will locate a leak while system is in a vacuum. I found a leak in a hose seal under vacuum. Haven't used it to listen to motor bearings yet but overall very impressed as a leak search tool.