The 5943001801 is a toroidal ferrite core manufactured by Fair-Rite Products for EMI suppression and inductance applications. It features outer diameter A of 22.1±0.4 mm (0.870 inches), inner diameter B of 13.7±0.3 mm (0.540 inches), and height C of 6.35±0.25 mm (0.250 inches), with a weight of 7.2 grams. The core exhibits a core constant (?l/A) of 20.7 cm?¹, an effective path length (l_o) of 5.4 cm, an effective cross-sectional area (A_c) of 0.262 cm², and an effective core volume (V_c) of 1.42 cm³. With an inductance factor (A_L) of 410 nH minimum, this core is suitable for power supply filtering, signal conditioning, and noise reduction in electronic circuits where compact size and reliable performance are required.