During Rod Serling's closing monologue, The Twilight Zone Theme can briefly be heard played in an unusual "Silent Movie/Honkey-Tonk Piano" arrangement, in tribute to the story's motif.
The old-fashioned clothes wringer that Buster Keaton is using to wash his pants in the beginning is the same kind of wringer that crushed his right forefinger when he was three years old. A curious little boy, he got his finger caught in the rollers and a doctor had to amputate it at the first knuckle. In this short, he gets the same finger caught in the wringer for laughs.
According to Rod Serling's promo in the previous episode, Richard Matheson wrote this script especially for Buster Keaton.
According to "The Twilight Zone Companion" by Marc Scott Zicree, producer Buck Houghton found Buster Keaton "absolutely wonderful" to work with. He even relied on Buster's comedic expertise to help perfect some of the gags in the story.
The dial on the "Time Helmet" starts at 1890 and ends at 1990, jumping at 10- and 20-year intervals