This set is distinctive, frankly, because of the slipshod way in which it was put together. The photos are of relatively poor quality, and the entire card front is printed in monochromatic blue. The caption and any dialog balloon for each photo is clearly done on a typewriter, with the card number apparently also pasted on.
The card backs are the standard for this card type, namely a humorous/horrific border surrounding a corny monster-themed joke, with the title at the top.
No definite information is knowwn about this set; but it is widely accepted to be printed (or at least distributed) by Rosan due to the similarity to that company's other 1960's monster offerings, Terror Monsters and Famous Monsters. Was this set then a trial run for either of these? Note also that both of these sets are also very similar to Nu-Cards' Horror Monsters set; in fact, two images are duplicated between Horror Monsters and this set. It is possible that Nu-Cards was the printer and Rosan the distributor, or some combination thereof.
Despite the lack of aesthetic beauty, young collectors should not be turned off by the Monster Cards set. The cards are kept and traded by both monster fans and vintage card collectors alike, and their basement-level design sense only adds to their charm as far as some enthusiasts are concerned.