The 2643665902 is a round cable EMI suppression core manufactured by Fair-Rite Products, designed to reduce electromagnetic interference in cable applications. This ferrite core features material grade 43 with burnished edges to remove sharp surfaces, and is available with a modifiable core length (C dimension) to suit specific application requirements. The core exhibits typical impedance values of 20 O at 10 MHz, 29 O at 25 MHz, 44 O at 100 MHz, and 58 O at 250 MHz, with a calculated DC bias field of 0.32 Oe for single-turn, single-ampere conditions. With a weight of 5.1 grams and outer diameter of 17.45 mm, this suppression core is ideal for cable shielding in instrumentation, data acquisition, and signal integrity applications where controlled impedance characteristics are essential.