Some more info about the AEM Tru Boost Boost Controller Gauge
The TRU-BOOST boost controller gauge includes an on-board 29 PSIg pressure sensor, built-in overboost protection with two timed shutdown levels, a scramble boost setting and a low-side output for a warning light. A 75 PSIa boost sensor for high boost applications is sold separately (please see TRU-BOOST 5 BAR Ugrade Kit).
AEM’s boost control solenoid is included with the TRU-BOOST controller gauge. It is specifically manufactured for automotive boost applications and will not corrode and stick from exposure to rich fuel mixtures or oil vapor. It is pressure tested to 100 psi and includes barbed fittings and -4 AN fittings to eliminate any chance of leaks.