Du-Bro Diameter Treaded Lightweight Wheel 7" (178mm) Part No: 700TL. Du-Bro Large Scale Treaded Lightweight wheels feature a foam interior yet have a tough and rugged exterior skin for durability. Excellent for paved runways! Hubs come with a 3/16" (5 mm) axle dia. opening and can be drilled out to 1/4" (6.35 mm). Features:
Lightweight
Shock absorbing
Fuel resistant
Built extremely tough
These also have many more applications in school projects and various crafts.