https://th.rs-online.com/web/p/transformer-cores/1701561
B66363G0500X187 | EPCOS N87 ETD 39/20/13 Transformer Ferrite Core, 326 nH, For Use With SMPS...
Buy EPCOS N87 ETD 39/20/13 Transformer Ferrite Core, 326 nH, For Use With SMPS transformers, Power TransFormers B66363G0500X187 or other Transformer Cores...