The guys make jokes about sex in almost every episode of the show (though there is no nudity, with the exceptions of the male sidekick not wearing a shirt in one episode; and in another episode the male sidekick taking off his pants on camera, which is censored). One experiment (a gigantic light bulb) is "almost as big as [Jon's] penis." Definitely at PG-13 level.
Jory calls his microwaves his girlfriends.
One experiment was a dildo.
Tagline: "Nobody likes roasted nuts," nuts being a slang term for testicles.
Lots of suggestive humor such as, after microwaving a banana, someone says "When was the last time you saw something that hot and six inches, Jory?"