Allow tractor as self-propelled working machine

It’s just that the tractor has a maximum speed of more than 20 km/h. It’s not the same as the tractor. It’s not the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor. It’s the same as the tractor.