Vintage (Late 1950's>)
OTC Owatonna Tool Co.  
# Z-914  
9-1/4" Special Adjustable Spanner Wrench
Adjusts from 1/2" to 2-3/4"
Ideal for adjusting pillow block bearings. 
Also, works well on the International Model “M” water pump or power take-off on all IHC tractor models.