---- July 19th 2024 ----

Call: 1 (800) 377-3244
Monday to Friday 8 A.M. - 5 P.M. (Pacific Time)
E-mail questions to:

Pricing is subject to change depending on product availability and backorders.
*Please Note: Contact us for items without price.

Cable RFI / EMI Suppression Cores


Split into two halves for easy application to existing cables.
AL (nH/Square Turn or nH/N2) is the AL value.
L is inductance in nH (nanohenries)
N is the number of turns of a wire
Required turns (N) = square root of (desired 'L' /'AL'), √'L' /'AL', or 1000 turns='mH' /'AL', (square rooted)
O.D. is the outer diameter of the core
I.D. is the inside diameter of the core
HT is the height of the core
LH is the length of the core
Hole type is the number of holes in ferrite core. Some may have multiple holes
CWS ByteMark Part Number is the part number to use to place purchase order. 1 inch = 25.4 mm
Color may vary by material and coating characteristics

Technical Data and Specifications

Low order fees are charged to total a minimum payment of $25.
Quantity marked in red is subject to availability and prior sales, or back order.
Orders are processed in 2 to 3 business days.
Please call for volume and price inquiries or email

Part Number:

EX: S-151-43-2P

S = Suppression Cores, 43 = Material Type, 2 = number of cores

Data enclosed in brackets, [ ], determines shape and characteristic.


  Part Number Material Description Impedance
@ 25 Mhz
@ 100 Mhz
Dimensions O.D/W x [I.D.] x LH x [HT] x (gap)(in.) weight (g) Quantity
on hand
  S-3851-43 43 Flat Cable Core
No Case
76 ohms
195 ohms
+/- 20%
1.500 x [1.050] x 1.000 x [0.475] x (0.075) 51.00 10 $4.00
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  S-551-43 43 Solid Flat Cable Core
No Case
76 ohms
195 ohms
+/- 20%
1.775 x [1.355] x 1.125 x [0.490] x (0.060) 71.00 80 $3.00
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  S-951-43-2P 43 Flat Cable Core
with Case
70 ohms
225 ohms
+/- 20%
2.670 x [2.050] x [1.272] x 0.320 110.00 36 $8.00
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  S-351-43-2P 43 Round Split Core with Case 110 ohms
225 ohms
+/- 20%
0.870 x [0.400] x 1.272 42.00 7 $3.00
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  S-251-43-2P 43 Round Split Core
with Case
110 ohms
225 ohms
+/- 20%
0.870 x [0.260] x 1.272 31.00 1232 $3.00
Buy Now

CWS Bytemark reserves the right at any time and from time to time to make changes to design, technical specification, or construction of any product listed on this website without notice.
CWS Bytemark also reserves the right to discontinue or limit sale of any product or service available throughout this website on temporary or permanently basis without notice.
CWS Bytemark highly recommend customers not to use its products offered on this website for inappropriate use and applications. Products should be tested for its suitability by prospective customers in all possible applications and conditions.

WARNING: This product can expose you to chemicals, which is [are] known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to

Any Comments, Suggestions or Questions? Contact us!
Tel: (714) 279-9010, Fax: (714) 279-9482
Toll Free: 1-800-679-3184 or 1 (800) 377-3244
CWS 353 West Grove Ave. Orange, California 92865

Copyright (C)2008-2021, CWS Bytemark
Updated 2021 Jan. Rev. V4.0