Toroid (type 43)

Ferrite Toroid, type 43 material. This model of toroid has been found by various hams to be a good choice for ununs for EFHW antennas, for an average power of up to about 40-50W.

Outside Diameter= 1.54 in / 39.1 mm /- 0.75 mm
Inside Diameter = 0.66 in / 16.75 mm /- 0.50 mm
Height = 0.875 in / 22.2 mm /- 0.80 mm

References:

- "Building an UNUN for an EFHW Antenna" article by Mike Dunstan G8GYW, in Practical Wireless October 2023