The device slows the synapses of people within a hundred meter radius of the wearer to 1/200 of normal. So in the vicinity it’s as if time had stopped.
Effects on people
Imagine the physics of the victim’s situation from a normal-time perspective, they’re moving at only 1/200th speed yet gravity still affects them normally. So if they try to run the same as usual-by leaning forward it seems from their perspective as if they’ve been slammed to the floor at amazing speed. The best way to move it by not leaning too far forward and trying to walk by dragging the feet.