1940s vintage "Astounding Science Fiction" pulp science fiction magazine. This is the issue from May, 1948. The cover art for this issue is by Alejandro and the stories are by L. Ron Hubbard, A. E. van Vogt, John D. MacDonald 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 "5 8" in ink on the bottom edge of the pages.