Repairable circular coil of various sizes according to the diameter of the pipe or bar to be checked. Polygonal (square, hexagonal, etc.) or shaped spools based on customer specification available upon request. MAIN FEATURES: – Type of winding: Differential or differential-absolute. – Sensor orientation: Circumferential; – Working frequency: 5-100 KHz; – Connection: Mil 15-pole. SIZES: Size 1: up to diam. 17 mm hole; Size 2: up to diam. 60 mm hole; Size 3: up to diam. 95 mm hole; Size 4: up to diam. 175 mm hole.