There are 2 styles in the Westclox Glo-Ben Pocket Watch Style Series
The Glo-Ben pocket watch was introduced in late 1917 or early 1918, and was the first luminous watch made by Westclox. In January 1929, the Glo-Ben was replaced by the Pocket Ben Luminous.
The trademark GLO-BEN was issued to Western Clock Co. on April 16, 1918. The registration contains the statement "The trade-mark has been continuously used in the business of said corporation since November 26, 1917."