The flag of Vietnam, also known as the "Cờ đỏ sao vàng" (red flag with a gold star), has the following properties:

1. Colors: The flag consists of two colors - red and yellow.

   • Red (background): HEX #DA251D, RGB(218, 37, 29)
   • Yellow (star): HEX #FFCD21, RGB(255, 205, 33)

2. Aspect ratio: The flag's aspect ratio is 2:3, meaning its width is two units while its height is three units.

3. Geometric properties and measurements:

   • The flag features a large, five-pointed yellow star in the center of a red field.
   • Each point of the star extends towards the vertices of an imaginary regular pentagon that is inscribed within an invisible circle.
   • The radius of this circle is equal to 3/10 of the flag's height.
   • The distance from the center of the star to the top edge of the flag is equal to half the flag's height.

These are the key characteristics of the Vietnamese flag without delving into its symbolism.