These Moroso tire pressure gauges are individually calibrated for accuracy within 2 percent. They feature a large-diameter dial face that is easy to read, and their hardened swivel chuck rotates a full 360 degrees for positive swivel attachment. Plus, the hose has a finger-operated air-bleed valve that allows you to release the pressure quickly and easily. With all of these great features, it's no wonder they're used by racers all over the country!