The LongHauler series by NewRay are models at 1/32 scale. These utility trucks are different from the cab-only models since the will be a little bit longer, depending on the particular model They measure about 12 inches to  long by about 3 inches wide by about 5 inches high (to the top of the cab). The hood and the main cab are made of diecast metal, everything else is made of plastic and plastic with chrome finish.
 
The doors can open revealing nice details. The wheels are made of rubber and they roll very smoothly, so be mindful of where and how you display it (don't have it roll off a table).
 
Particular to the dump truck model, the bucket can be tilted and you can see a very nice arm that can extend. Moreover, the tailgate does pivot at its hinges.
The second dump bucket attaches to the truck and it too has the same arm and tail gate articulation as the main bucket.
Together the truck and both buckets measure about 22 inches long. 
These models come in individual window boxes.
 
Note that these are not really toys. They would not survive being played with regularly.
 
The W900 is a Kenworth Class 8 truck model, known for its long-nose style. Even as more aerodynamic models such as the T600 and succeeding versions have been introduced for fleet use, the stylish W900 remains in production due to its particular popularity with owner-operators. The W900 was a gradual introduction, retaining many features of its predecessors which also continued to be sold alongside it in the early 1960s.
 
The box measures 24" x 4" x 7" and labeled for 8 Years and older.