These Schumacher Racing Products o-rings are a factory replacement for the Cat PB 4x4 buggy platform. Sold in a pack of 4, they are sized at 6x1.5mm for precise fitment in the drivetrain and gearbox assemblies that require this specification. Keeping fresh o-rings on hand helps maintain a proper seal and reliable performance in the drivetrain. Features: 6x1.5mm o-ring specification Pack of 4 Designed for the Schumacher Cat PB platform Drivetrain and gearbox application 7/7/26 cs