Coax to hdmi converters usually come as adapters.
Hdmi converter to coaxial cable.
Coax to hdmi converter.
Hdmi to coaxial rf converter for old tv hdmi in coax out transmitter box with f type male to pla 9 5mm coaxial cable remote control zoom function 1080p input analog signal rf coax output adapter 3 5 out of 5 stars 7.
Many new televisions do not offer a coaxial cable input but older cable boxes do use a coaxial cable output requiring a converter to make the connection.
This page on amazon has a bunch of them for sale.
Shop for coaxial tv cable converter to hdmi at best buy.
Those with larger av setups may want a more involved convertor unit but for the rest of us a simple coax to hdmi converter box will suffice.
Other retailers will offer the same kinds of products too.