The One Where Chandler Doesn't Like Dogs - S7-E8
Visible crew/equipment: When Chandler sees the empty dog basket on the floor at Ross' there is a panning shot to the door. If you look carefully, you can see a crewmember wearing blue jeans and white shoes. (00:17:25)
Answer: Usually by the seventh night of Hanukkah you don't know what to get the other person, and you will probably resort to getting the other person something insignificant. Chandler is basically saying that the pen is a stupid gift.