Today's set is an insert from the 1966 Topps set, Rub-Offs. This is another insert that is not the easiest to collect. When kids got the Rub-Offs, the rubbed them off. That was fine for the kids of 1966, but not so good for collectors 50+ years later.
The set has 100 players plus pennants for each team. There are five Cubs because 100 ÷ 20 teams = five players and back then Topps did things much more evenly among the teams. You'll notice that most of my rub-offs have centering issues. I went the budget route when buying. Some day I can upgrade.