The CR3.4 Sherpa is a high-end scale crawler with technical features that are exceptional for an RTR vehicle. A realistically designed 5mm CNC machined aluminum frame with a heavy duty aluminum 4-link suspension system. Oil-filled shocks with internal springs, 5mm piston rods and shock bellows provide a silky smooth and realistic response. Portal axles not only offer a greater distance from the differential housing to the ground than conventional axles, they also have another positive feature. In conventional crawlers, torque applies so much force that the vehicle jumps over the obstacle. The design of portal axles reduces the gear ratio at the wheels and virtually eliminates torque shocks from the drive. The overall reduction ratio of the axle drive is more than double that of non-portal designs to allow smooth running.