Lionel O Gauge Diecast Metal Sprung Trucks with Rotating Bearing Caps Model Train Parts Accessory will be a great addition to your train collection. Pack includes (2) O Gauge Diecast Metal Sprung Trucks with Rotating Bearing Caps to use as replacement parts. Compatible with Lionel O Gauge System and features metal construction, rotating bearing caps, metal coupler armature, quick and easy to install, adds weight and improves tracking, and you can upgrade your rolling stock trucks.