Antique and from the same estate sale....
 
Model A100.  THIS IS AN EARLY SHAPLEIGH HDWE CO. ST LOUIS MO. POCKET KNIFE.  MADE IN THE USA.  The company started making hardware tools around 1868.  I would guess that this is from around the turn of the century...maybe right before.
 
"Hawkbill" design single blade.  Brown wood handles.  PLEASE SEE PICTURES.
 
Condition:  Handle has no cracks or chips.  The blades have some signs of age but no chips.  One pin looks to be a replacement.  Opens and closes good.  Light snap left.  Keep the patina or refurbish.  You can see the "A100" text as seen in pictures but the Shapleigh tang stamp is unreadable.
 
4" long when closed.
 
Location E2