Ferrite Toroid

Type 43

Outside Diameter= 2.40 in / 61.0 mm +/- 1.30 mm
Inside Diameter = 1.40 in / 35.55 mm +/- 0.85 mm
Height = 0.50 in / 12.7 mm +/- 0.50 mm 

Perfect for chokes, baluns  

Genuine Fair-rite