Al alloy track GR-01E, specifically designed for material testing using the free space method. The track can hold two antennas of the same type, either lens horn antenna or focusing lens horn antenna. The focal length between the two antennas can be set, and the focal length can reach 500mm. A sample holder is placed in the middle of the track. Antenna models that can be mounted on this track are: LB-CL-12-18, LB-CL-15-30, LB-CL-28-60, LB-CL-42-20, LB-CL-42-30, LB-CL-65180-70, LB-CL-75180-70, LB-CL-90-70, LB-CL-180400-20, LB-CL-180400-30, LB-CLS-12-18-10, LB-CLS-15-30-10, LB-CLS-28-60-10, LB-CLS-65180-70-10, LB-CLS-65180-70-50, LB-CLS-75180-70-10, LB-CLS-75180-70-50, LB-CLS-90-70-10, LB-CLS-90-70-50, LB-CLS-28-70-20.