Lot of 12, Red, Iron Powder Toroidal Core, 2 Material, Frequency Range 2 Mhz - 30 Mhz, 0.68" O.D. x 0.37" I.D. x 0.19" Hgt. U=10. Alltronics part# T_68_2. Datasheet : http://www.alltronics.com/mas_assets/acrobat/T_68_2.pdf