Uncategorized
Inventor
Electromagnetic relay
Elevator control
Elevator control
Elevator control providing preferred service to hall calls...
Elevator controls
No associations
LandOfFree
L. Hall Donivan does not yet have a rating. At this time, there are no reviews or comments for this inventor.
If you have personal experience with L. Hall Donivan, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and L. Hall Donivan will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-P-629284