The bicycle is from the international brand Trek, and the model is Trek 3500. Classification: Mountain Bike (MTB). Usage: Designed for off-road and unpaved trails, and also suitable for daily use within the city thanks to its front suspension. Bicycle Size 1. Wheel (Tire) Size It is clear that this model (3500) often comes with 26-inch wheels. This is the traditional size for mountain bikes that provides good control and ease of movement.