Review on Zefal Twin Bicycle Tire Gauge by Matt Norwood

I have an OLD Zefal Presta sensor that still works after 15-20 years! I needed another for a second bike and also liked the flexibility of the Schroeder option. This brand new gauge seems to read about 10psi lower than several other gauges I have. I plan to do a final test with a digital pressure gauge. I'm discussing returning it for another and if it's not better I'll get a refund. 10psi isn't a big deal on a mountain bike, but 10psi on a road bike makes a world of difference, especially when you're riding close to the max! I wouldn't want to inflate a tire because I inflated it too much.