Welcome to Propulsion Timepieces.
 
Here we have a hand tool used to remove screw down watch back covers.
 
Used for battery replacement and to access the internals of the watch for the purpose of servicing.
 
The short tool is suitable for watch back cover from 9mm to 40mm.
 
The long tool is suitable for watch back covers from 10mm to 50mm.
 
A must for any watch collector.