One Panel #496-498: Knocking Heads

From "The Lightning King" by Otto Binder and the Jack Binder Shop (possibly Ed Dobrotka), Bulletman #3 (January 1942)

No, Bulletman! That's not how you do it! Show him, Green Lantern!

From Green Lantern: "The Building Racket" by Bill Finger and Irwin Hasen, All-American Comics #34 (January 1942)

THAT'S how you do it! Who else can show him? Flash?

From "The Adventure of the Duplicate Faces" by Gardner Fox and Everett E. Hibbard, All-Flash Quarterly #3 (December 1941)

What's really important when you're knocking heads is to not be seen, apparently. Now you know. And knowing is half the battle.