Product Name: Ferrite Ring;Each Size: 33 x 19 x 11mm/ 1" x 0" x 0" (Outside Dia.*Inner Dia.*T) Material: Iron Color: Yellow, White Net Weight: 83g Toroidal shaped. Used for top temperature inductors. Iron powder core is usually saved near indicators of place. It has isolation eddy current, low permeability and constant magnetic characteristics. Package Contents: 2 x Ferrite Ring Only the above kit content, other item are usually not included. Note: Light and different reveals can cause the color of the item in the photograph a little bit varied from the real thing. The measurement allowed error is +/- 1-3cm.