High torque motors are virtually just a regular, internally commutated brushless DC Motors mounted with extra gear mechanism at the top, to either raise the torque or to decrease the RPM (Revolutions each and every minute). These DC motors are noiseless powerful and can be utilized in several hobbyist and industrial application.
Reducing the RPM whilst maintaining high torque might require adding up more complex gear mechanism therefore the expense of these High torque DC motors mostly depends on the RPM, torque and quality of the motors.The electric motor shaft from the bottom engine though a transmission connects the small gear box fixed at its front portion, which generates the necessary torque while keeping the RPM low, the entire gears and gear heads are doped with thick viscous grease lubricant.
These High torque Motors seriously various RPM’s such as for example, 5 RPM, 10 RPM, 100 RPM, 300 RPM, 1000 RPM and so on. The expense of these geared motors is based on the RPM, usually lower RPM costs a lot more than 
those of higher RPM.
Applications
High torque and low rpm DC motors are well suited for robotic and hobby applications, thought the size of the electric motor is a matter of concern because it is quiet huge in size due to additional gear box but still it would save the trouble and cost of adding exterior gears to the assembly of robots where just the regular DC motors Stainless Steel Chain wouldn’t do well. The High Torque, Low RPM DC motors comes with inbuilt gearbox system providing required torque for your robotic software. Hence these motors would be the many favorable choice for the hobbyist robotic projects and tutorials posted here.