Inside front cover.
takes place after 1st story in Green Mask, The (Fox, 1940 series) #1
Blue Beetle wears business suit, mask, and hat in this story; no apparent super-powers; story chronologically follows 1st story in Blue Beetle (Fox, 1939 series) #1
This Blue Beetle was published by Fox, then Holyoke, then Fox again, and then Charlton before Charlton revamped Dan Garrett Blue Beetle with a new origin and powers in 1964, and later replaced him with a new Blue Beetle (Ted Kord) in 1967.
Throughout his early appearances, the Blue Beetle's last name varied between "Garret" and "Garrett", while Mike Mannigan sometimes had his last name spelled "Manigan".