Rubbish product :
Took measurements 5 times in a spend of 3.5 minutes and it all gave erratic readings:
86/39 pulse 76
175/ 132 pulse 73
140/ 72 pulse 72
144/ 78 pulse 75
157/ 92 pulse 72
Checked with a traditional BP machine and reading was 116/83 pulse 72
Don't waste your money...