Check the listing for details. 25 pcs. Ferrites Small Binocular Cores! Wind your own transformers, etc. NOS. Condition: Open box. Listed at 9.00 USD. Here are 25 pcs. of new old stock small ferrite binocular cores, useful for winding RF components such as transformers, VSWR bridges, chokes, etc.may be power dividers. Please observe the dime lying in the bottom left of the picturer, gives you an idea of scale. The binocular cores are small, like .245 inch long, by .270 inch wide, by .160 inch thick or so, not for very high power. Hole diameter is approximately 1/16 of an inch in diameter. I do not know the core material, as they have a customer coded part number, but assume good up to at least low VHF based on where they came from. Anyway you get 25 pcs. of "binocular" 2 hole ferrites here, not so common to find, from military/spook receiver maker Watkins Johnson! Nice for baluns etc., if you tinker at HF/VHF (FET mixers?). Thank you. I combine items for lower shipping. Check out my other items for more RF stuff! Be sure to add me to your favorites list!