Listed in the 1939 Radio Shack catalog as the "Learner Set" for $2.94.
Sold as the "Sr. Learner Set" in 1920 for $5.00.
Sold as the "Learner Set" in 1941 for $5.57.
Another Signal Electric brochure listed it as "Standard Telegraph Set" for $7.65.

Here's the text from the 1941 brochure:
On city, private and short lines learners will find this instrument easy to handle and having a clear, distinct tone. Bar frame and key base are black enamel, the bridge is brass, sounding bar is aluminum with black lacquered steel sounder plate. Key lever is nickel plated. Sounder and key are mounted on a mahogany finished wood base.