https://www.ruitrailer.com/introduction-and-characteristics-of-selfpropelled-modular-transporters-spmts.html
INTRODUCTION OF SELF-PROPELLED MODULAR TRANSPORTER (SPMT)
The self propelled modular transport is a platform vehicle with a large number of wheels. It is used to transport large objects such as bridges, oil refining equipment, motors, and other objects that are too large or heavy for trucks. However, trucks can provide traction and braking for SPMTs when going up and down hills. SPMTs are used in many industries around the world such as construction and oil industries, shipyards and offshore industries, highway transportation, factory construction sites, and even for moving oil platforms.