Simple product, convenient, well thought out, comes with a nice pouch. The directional valve tip is very well thought out and allows easy adaptation, this is rarely the case otherwise. The display is very readable, the product seems good quality workmanship. Unfortunately no calibration certification or even characteristic precision is specified, that for me it's really unfortunate for a security product ... However to be sure of this I have been compared with a certified gauge, the displayed precision is identical (2.2 bar)