Du-Bro Micro Sport Wheels 1.23" (31mm) Part No: 123MS. These open spoke wheels will add a sporty look to your model. They have been designed with electric models in mind. These also have many more applications in school projects and various crafts. Wheel Dia. = 1.230" (31mm), Axle Dia. = .047" (1.2mm), Weight = 1.1 grams/ea.