I believe you are supposed to use them on the left wrist onlyI just got the omron gold bp4350 off Amazon last week. It's within 5-10 points of my 10 year old omron arm cuff model. It says it has Bluetooth and I like the idea of having a record on my phone but I've yet to test out that functionality to see how well it works yet. I like that it has a light that will come on when your wrist is at the right height bc that's always my biggest problem with the wrist models. The weird thing with every wrist brand I've tried so far is they don't worry on my right wrist. Has anyone seen this before? With the arm cuff both arms have the exact same reading. With the wrist cuffs I've tried my right wrist is always 50 points higher on both numbers! Freaked me out the first time for sure