Here's a Rare Waltham XA Military US Army Aircraft Clock. 

Made by the Waltham Watch Co in 1916 for the Aviation Section of the US Army.

The specially adjusted size 37 movement is a 8-day, 7-jewel mechanical type.

Dial is 2-7/8" across, marked  A.S.S.C. U.S. ARMY, Case is Aluminum.

The movement has been ultrasonically cleaned,oiled and adjusted.

Clock looks and runs great and keeps accurate time.

This is a super nice Waltham, great for any collection!