Works well. Easy to connect to XTRONS main unit. The gauges are a bit chunky, about 4 quarters tall, and it's a PITA for pressure adjustment because I have to remove the lock nut. Seems accurate. No way to calibrate, at least I haven't found it. UPDATE: A little over a year later, one of them showed a low tire, but it's hard to take it off. I removed them and had to cut the lock nuts with wire cutters. Hopefully they won't fall off without the lock nuts, but they seem a little disposable asβ¦