Choosing a skimmer based on size speculation can be a costly mistake. Buying the smallest skimmer available because it is the cheapest or purchasing the biggest skimmer because you think it will work faster will not lead to successful skimming results.
A belt is to a skimmer like wheels to a car’s chassis: although the latter is the most identifiable part, it needs the former to actually run. Just like tires, belts are not one size fits all. Just as there are snow tires, street tires, year-round tires, and more, so too are there a variety of belt materials. So what purpose does each serve?