Here is my WW1 US Military timepiece collection A.S.S.C. stands for Aviation Section Signal Corps a Aircraft clock made by Waltham Model XA 7 jewel 8 day movement. My US issued wristlets Elgin Pershing dial issued to the 29th div. in WW1 and the Zenith US Army Signal Corps possibly issued to Pilots since the Air Service was attached to them in WW1. Case back from the Elgin with the info of the 29th div.