At the office party, they fill up the water cooler with creme de menthe, which is a bright green. However, when they fill up a glass, the liquor comes out as clear.
When Draper is on the train in uniform the overseas service bars are on the wrong sleeve.
A song titled "Hot Dog! Here He Comes!" is played during the office party. It is the B-side to a record released by The Tri-Lites in 1963, three years after the time this story takes place.
Don's flashback to Korea is dated 1950 and appears to be summer, indicating the beginning of the war, yet Lt. Draper references the Chinese as the enemy. China entered the war in November 1950, at the onset of the Korean winter.
We have seen a photo of Dick and Adam Whitman dated 1944. Adam appears to be about 8 or 9 years old. In this episode Dick/Don looks out at the train platform in 1950, at his stepmother Abigail, her husband, "Uncle Mack," and Adam, who still appears to be 8 or 9.