Version: 2018.1
public Vector3 size ;

Description

The size of the box area in which reflections will be applied to the objects. Measured in the probes's local space.

Размер куба будет масштабирован в соответствии с масштабом transform-а.

    ReflectionProbe probe = GetComponent<ReflectionProbe>();
    // Make the area long
    probe.size = Vector3(10, 1, 1);