ventilation equipment for residential use, namely, ventilation controllers and alarms responsive to the controllers that signal failure conditions

electronic pressure switches for annunciating and monitoring the pressure point at which bursting disks rupture for use with refrigeration and air conditioning chillers

LIQUID LEVEL INDICATORS FOR LIQUID FUEL TANKS AND THE LIKE

INDICATING DEVICE FOR USE WITH LIQUID CONTAINING TANKS AND COMPRISING AN AUDIBLE SIGNALING MECHANISM FOR INDICATING WHEN THE LIQUID LEVEL HAS RISEN TO A PREDETERMINED POINT AND A VISUAL GAUGING MECHANISM FOR INDICATING THE LEVEL OF LIQUID IN THE TANK