[CONTROL PANEL INSTRUMENTS]. An event indicator that would give a gray or "barber pole" indicator flag on the results of certain control panel actions. Over 30 of these were in the Command Module -- A circular dual indicator meter with the left meter measuring the difference in pressure between spacesuits and cabin in inches H20 + or - 5. The right meter measures the total rate of flow of oxygen supplied to the environmental control system downstream of the main regulator valve in LB/HR [pounds per hour] from 0.2 to 1.0 -- A rectangular dual indicator meter that measured pressure of the service module cryogenic hydrogen tanks with a measurement range from 0 to over 300 PSIA. The unit came from the Command Module ground trainer used by astronauts in Houston, Texas. All were made by Weston Instruments, Inc. (3)