Feature: Core iron powder is stored near place signs It has parasitic current insulation, low permeability and constant magnetic characteristics Stable and reliable performance and durable use Used in power transformers, current transducers, measurement transformers, inductors, chokes, reactors, voltage stabilizers and regulators, welding transformers, broad band transformers, filters etc. Brand new Model: T50-26 Material: Iron Color: Yellow, White External Diameter: approx. 13mm/0.51" Inside Diameter: approx. 7.5mm/0.295" Thickness: approx. 5mm/0.2" Circumference: approx. 3.19 cm Area: approx. 0.112cm Volume: 0.358 cm Inductance Coefficient: 33.0nH/N Permeability: 75o Quantity: 50 Pcs/1 Set Note: Please allow 0-3mm error due to manual measurement. pls make sure you do not mind before you bid Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! No Retail Package Package Includes: 50 x Toroid Ferrite Cores