Even when hydraulic system (brake pedal) fail, mechanical hand brake drum structure still provides considerable braking power. Drum in disc brake system is the most complete system. Drum brake is a very stable and inexpensive brake system, is widely used in the truck system. The disadvantages are its delay of reaction and not able to withstand high temperatures. ※ When water intrudes, drum brakes need to rule out water completely to the proper functioning. Drum in Disc brake System in addition to its cost is relatively high, almost equal to the complete brake system. Performance cars are equipped with four-disc for its original braking systems.(Ex. Porsche, Ferrari, BMW, Mercedes…etc.） When the handbrake on the caliper, as a single system (composite caliper), you can get the advantages of both. The only problem is that its hand brake is unable to afford a larger load, when the load is large, this means there is a greater risk. This is why the high loading vehicle will choose a cheap drum system, or expensive drum in disc dual system. The composite caliper is almost non-existent in this field. Upgrade the rear brake system is definitely the right choice, provide safe and reliable brakes is the UPI’s mission! Whether you just want to upgrade to a disc with drum dual system, or off road use, even to race on the track, you will need to match racing calipers and large-size disc. A reliable and stable drum in disc system or drum mechanism is only UPI!