The EM152 measures differential, positive or negative pressure. Units can be selected from any one of 11 options including; inH2O, psi, bar, mBar, kPa, InHg, mmHg, ozin, FtH2O, cmH2O and kgcm. Features pressure zero, hold and record. A simple hose barb allows for quick tubing connections. And is backed by a 1-Year limited warranty.