Sliding probes operate in reflection mode and are useful for inspecting rows of fasteners for surface and near-surface cracks.

                             Thunscrew          Manual
Frequency             Adjustment         Spacers
50Hz-1KHz            ASLD-50H-A        ASLD-50H-A
100Hz-20KHz        ASLD-100H-A      ASLD-100H-A
500Hz-50KHz        ASLD-500H-A      ASLD-500H-A
1KHz-100KHz        ASLD-1K-A          ASLD-1K-A
10KHz-500KHz      ASLD-10K-A        ASLD-10K-A