The CPA 2501 from Mensor Corp., San Marcos, TX, is a digital pressure gauge that incorporates avionics functions to indicate altitude and airspeed. Two independent sensors characterized to 0.01% F.S. pressure measure altitude/altitude rate on one channel and airspeed/airspeed rate on the other. An optional barometric sensor is available for display on each channel or as a separate channel. There are four possible configurations: Ps/Qc with a virtual Pt channel; Ps/Pt with a virtual Qc channel; Ps standalone altitude version; and a Qc standalone airspeed version.