Professional Manual Blood Pressure Monitor Kit - Accurate Desktop Sphygmomanometer with Durable Carrying Case for Home & Clinic Use | Reliable BP Measurement for Health Monitoring

First the quality and functionality of this unit is wonderful, I see nothing wrong with it, 5 out of 5 stars!If you know what you are doing (I do), you don't need instructions you are good as gold.If you do need instructions your going to have to find them the internet (very easy!).So yes, I took off one star because this product is 100 Chinese no English to be seen anywhere. However, you don't need any English on the device. The numbers are standard (English), that's really all you need.Well... It would have been nice to see the cuff size in English so you know for sure it's the right size, but alas, it's all in Chinese. So you just have to trust it is as stated in the description - 22-32 centimeters.But seriously, this type of device could last 20 years or more until the plastic, cloth parts rot, they are cheap and easily replaceable, available. I bought this unit to test all the other professional digital units in our offices. It's easy, just hook up the inputs of your digital unit with a Y connector directedly to the input of this mercury one. Reading should Be very close. Also on YouTube.As long as you learn to use this Mercury unit correctly (it not hard!), you will have the most accurate system in the world. I'm serious. THIS is the Mercury Standard, the device all the others are checked calibrated to.PS: The reason it's all in Chinese is because they are outlawed here in the US (except professional use), you can't make these in the us. Mercury is not something you want to toss in the trash, even many, many years from now. This requires special disposal, few people would take the effort to protect the environment.