With an equivalent item in 1 month, the needle was disengaged. Because pulsation is intense, I think that it can not be helped. The thing is simple drip-proof, I think that this price is cheap. However, I think that it is better to tighten the attachment screws of the dial and the cover.
I used Emmon's air gauge for about 15 years ago, but this time I decided to make it own because I was doubtful about the accuracy and the meter size was small and my presbyopic subject was hard to see. Accurately it was a difference of -10 KPa, but the display part was large, making it easier to see and ease handling.