The EPCOS - TDK Electronics T102/66/15 series toroid ferrite core is an ideal transformer and inductor component. It is made of K10 material and has an initial permeability (µi) of 700. The core factor (ΣI/A) mm^-1 is 0.96, effective length (le) mm is 255.3, effective area (Ae) mm² is 267.3, and effective magnetic volume (Ve) mm³ is 68220. This core has an inductance factor (Al) of 900 nH and is ungapped. Its diameter is 4.016" (102.00mm), height is 0.591" (15.00mm), and it comes in a box package. The core is uncoated and has a tolerance of ±25%. It is suitable for use in various magnetics applications.