Mid-century vintage, early 1950s pulp science fiction magazine, "Astounding Science Fiction" from January, 1950. The cover story for this issue is "The XI Effect", by Phillip Latham. There are also stories by Poul Anderson, Isaac Asimov, Rene Lafayette and others.

This is in nice vintage condition. We don't know anything about grading pulp magazines, but this issue does have light wear and age. There is a small tear to the front cover (near the date) and a "10" in ink on the bottom edge of the pages.