The description reads as follows;
The HiTechnic IR RC Car features the new HiTechnic Infrared Receiver. This sensor makes it easy for you to control your creations using a LEGO Power Functions Remote.
This model is based on the LEGO Mindstorms 1.0 set. It also requires a LEGO differential and that is not part of the Mindstorms set. If you do not have a LEGO differential, you can go to bricklink.com and search for "Gear Differential", the part number is 6573.
Remote control - Using the HiTechnic Infrared Receiver and LEGO Power Functions Remote
Steering uses a PID controller Both NXT-G and NXC sample programs implement a PID controller to steer to a specified target position.
Ackerman steering - Which means that it has a steering geometry so that in a turn the inside front wheel turns sharper than the outside wheel.
Geared up to differential - Geared up 3:5. The drive motor has a 40 tooth gear driving the 24 tooth side of the differential.
Building instructions and sample programs can be downloaded from www.hitechnic.com