Amazing Stories vol. 17, no. 6 (June 1943)
I wasn't sure if the guy on the right was a giant or the one on the left was tiny but the word "mites" in the title says it's the latter.
The snarl on his face contrasts with the relative calm of the victim. Really Dave, you're putting me into the retro-encabulator? OK I guess.
Original magazine: https://archive.org/details/Amazing_Stories_v17n06_1943-06_cape1736