65mm; Core Material Grade:77; For Use With:Output Chokes, Power Input Filters & Transformers and HF Fluorescent Ballasts; Effective 52Y1655.TRANSFORMER CORE, U, 77; Core Type:U; Core Size:41.7mm x 20.5mm x 11.
25mm; Core Material Grade:77; For Use With:Output Chokes, Power Input Filters & Transformers and HF Fluorescent Ballasts; Effective 52Y1658.TRANSFORMER CORE, U, 77; Core Type:U; Core Size:31.5mm x 10.