The design of the Ohm was underpinned with scientific research at the Institute of Mechanical Handling and Logistics (IFT), Stuttgart, Germany. It is an assisted braking resistor which is attached to the first bolt in the safety chain. In the event of a fall, the rope is pulled into the braking unit of the device and the fall is progressively arrested. This means the OHM does not brake the rope abruptly, but incrementally, so that the fall can be dynamically caught by the belayer. The OHM increases the friction in the safety chain, regardless of which belay device is used. This means the belayer has to apply considerably less manual force to the brake-side of the rope and is not suddenly pulled upwards or against the wall.