EGLOFF & CIE TURGI (SUISSE)
Up until 1907, the company was called W. Egloff & Cie in Turgi, Switzerland.
From 1909 on, the company's name was W. Straub-Egloff & Co., Turgi
Marked A-912 = INFANTRY BUNKER LOCATION - NATIONAL REDOUBT
Officially documented by the Swiss Army Museum. The officials provided the exact coordinates of the bunker in which this Lantern was used.
(See Google Earth View above)
You can be fortunate enough to find a "Helvetia", but not this particular model with the military markings. This lantern has been indoors its whole life and when it came into my possession, it had not appeared to have been lit. Extremely rare