All four are 1.25" and from the 1940s. Buttons are:
The Phantom Club Member
The Phantom's popularity in Australia continues to this day. Australian issue features "The Phantom's Club - Member" text around rim. Classic Phantom premium.

Shield G-Man Club
The Shield was one of the most popular comic book heroes of the 1940s, fighting to protect the American way of life in a patriotic costume that made him invulnerable. In fact, The Shield was the first hero to wear such a costume, introduced in Pep Comics #1 in 1940, pre-dating Captain America by over a year. The Shield also appeared in Shield-Wizard Comics between 1940 and 1944 and the character's popularity gave rise to The Shield G-Man Club. Button was issued by Pep Comics in 1943, featuring classic image of The Shield bending metal beam w/ "Truth - Justice - Patriotism - Courage" code and "Shield G-Man Club" name at top.

American Eagle Defenders
Rare patriotic button depicts The Eagle, a comic book character who made his debut in Science Comics in 1940 before appearing in four issues of his own title in 1941-1942. Button issued at that time to members of the "American Eagle Defenders" club, the name appearing on this button.

Ato McBomb
Button features atomic bomb-inspired character created/illustrated by Clarence Matthew Baker (1921-1959),  the first known African-American artist to find success in the comic-book industry, best known for drawing heroines like the Phantom Lady (gaining a reputation as one of the best "Good Girl" comic artists of the Golden Age) as well as Romance comics. Baker is also known for creating the first known black hero in American comics - Voodah, who debuted in Crown Comics #3 in 1945.

Backs have either trace of oxidation or wear to the silver finish. Fronts have lt. wear mostly only seen upon close inspection and/or in reflected light. All remain bright and glossy. Philip Samuels Collection.