Michael Mauser Private Eye: The Gredown edition

Gredown's Michael Mauser Private Eye was published c.December 1976:

The cover art is unsigned but looks like the work of Phil Belbin, and is based on the opening panel of the story The Inheritance:

Michael Mauser began as a support character to E-Man, and then appeared in his own back feature in Vengeance Squad. This issue reprints all the Michael Mauser stories from the six issues of Charlton's Vengeance Squad, as well as a Vengeance Squad story and a horror story introduced by Mr. Dedd. This issue is fully indexed on the GCD.

This issue appears to be the first collection of Michael Mauser stories ever published.

And I like the frizzy cats on the cover.