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- July 14th 2020 -
Call: 1 (800) 377-3244
We Are Open Monday to Friday From 8 A.M.- 5 P.M., (Pacific Time)
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Ferrite Toroidal Cores


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)
CWS ByteMark Part Number is the part number to use to place purchase order. 1 inch = 25.4 mm
O.D. is the outer diameter of the toroid core
I.D. is the inside diameter of the toroid core
HT is the height of the toroid core
Color may vary by material and coating characteristics
Parts are RoHS compliant

Technical Information
For other product details refer to:

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: (Type - Size (inches) - Material/Coat or Mix) where C stands for a coat type (see PDF)

Ex: F-23-43   F = Ferrite Toroidal,   0.23 = O.D. Dimension,   43 = Material Type or Mix

O.D. is divided by 100 to get measurement in inches

Limited product may be carried under a similar name to that of other companies  

  Part Number AL
O.D. x I.D. x HT
Material Initial Permeability Alternate
Part #
on hand
ZW-42507-TC 7825 1.000 x 0.610 x 0.312 W 10000 ZW-42507-TC 0.374 6.17 11.60 23 $1.53
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ZW-44916-TC 11800 1.932 x 1.332 x 0.625 W 10000 ZW-44916-TC 1.160 12.70 75.30 816 $8.50
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ZW-46113-TC 13690 2.400 x 1.400 x 0.500 W 10000 ZW-46113-TC 1.560 14.50 117.30 40 $19.89
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ZW-48613-TC 11040 3.375 x 2.187 x 0.500 W 10000 ZW-48613-TC 40.200 21.50 203.00 25 $29.40
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Disclaimer: 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! Email:
CWS 353 West Grove Ave. Orange, California 92865
Call us Toll Free: 1-800-679-3184 or 1 (800) 377-3244
Tel: (714) 279-9010, Fax: (714) 279-9482

Copyright (C)2008, CWS Bytemark
Updated 2013 Jan. Rev. V3.1