Kramer's unoffical catchphrase "Giddy Up" is first used in this episode.
When Jerry and George are walking down the stairway and takling about Red China, they are walking side by side. In the nest shot after they round the corner, they switched places.
When Kramer finally finds the car and is putting the box in the trunk, a hand (George's?) reaches to help with the trunk door. In the next shot the hand is gone.
At the end of the episode, when Kramer is struggling to start the car you can see George, Elaine, and Jerry giggling. This is because the car was supposed to start but the fact that it died was so unnexpected that they couldn't hold it.
Babu is from Pakistan, but Brian George is from Israel.
In the first scene inside the Dream Café, Elaine orders Rigatoni, but when she moves tables to work on the test, you see her food is quite clearly a plate of Franks and Beans, not pasta at all. This is what Babu offered Jerry at the start, and what he spills on the test later in the episode.
A minor goof on George's part, but it's impossible to get a 1409 on the SAT because the scores only go in increments of 10.
George pulls out his wallet to extract a piece of paper with the phone number on it as he sits down to make the call to China. He has a normal thickness wallet here, instead of the bulging file cabinet of a wallet he carries in the episode "The Reverse Peephole."
After everyone yells at Kramer for watching the "before footage" on Jerry's VCR, he says, "All right, I'm gonna go take a look at this." and leaves. However, he leaves without removing the tape from the VCR, thus having nothing to "take a look at."
When Kramer returns to look at George's head the second time, before he leaves he says "Ok I'm guna go take a look at this". He had no reason to say that because he hadn't recorded anything new to look at.
In Kramer's "before" shot of George's head, it looks like his head is shaved in the middle rather than being naturally bald. This is easier to see when they look at the tape on the TV in color for comparison than when Kramer is actually making the video.
When Kramer takes the number from Jerry he tears it 3 times. When he throws it up in the air in another scene there're many more pieces than before.
George says to Jerry that the penis "wins until your forty" but Jerry Seinfeld was nearly 40 at the time of the episode.
While Elaine is looking through the closet, Kramer strikes another match and begins to light his already lit pipe. When the landlord starts talking to him, the match is gone and he puts his hand in his pocket!
Elaine tells someone at the party that she is reading manuscripts for Pendant Publishing. Jerry walks by and says "Pendant! Those bastards!". This is a reference to what Elaine's father said in "The Jacket" when Elaine told him she was working for Pendant.
In another reference to that episode, Kramer tells Steve a story that involves a magician and someone almost getting hit by a car. Although we don't here the entire story Kramer's probably telling Steve about when he and Elaine picked up his friend's doves.
Jerry says he's 36 years old, and we assume that George is the same age. This is only episode where any of the main characters age is mentioned directly.
When Jerry is writing something on a notepad at the party, he does it with his left hand.
One of George's co-workers says she just sold a property at 129 W. 81 Street. That's the building where Jerry and Kramer live.
At the party, the guy going on and on about peanuts to Elaine says that the cashew is a legume. It is not. The peanut is (grows in a pod), but the cashew is the seed of the cashew tree.
Just before Mr Pocatillo leaves Jerry's apartment, before he goes to kiss Patty's hand, the door is wide open, yet he goes to kiss her, and starts to leave and the door is shut. Jerry didn't close it or anything, Just a continuity error.