Harry Sterken:
Heavy pushing
Harry Sterken:
Excavator booms
Harry Sterken:
Excavator bucket teeth
Harry Sterken:
Dozer controls
Harry Sterken:
The Ripper
Harry Sterken:
"Tulsa" crane
Harry Sterken:
Mighty Machine
Harry Sterken:
Cat drive train
Harry Sterken:
Dozer driving mechanism
Harry Sterken:
Glass ball and heavy equipment