Victory Decoration.

[Taz]

This PAVN Decoration is also linked to an Order of the same name with identical appearance, only the size and suspension device tells them apart, it is smaller than the Order.
It is inscribed CHIEN THANG (Victory)
Awarded in two classes to those personnel who did not meet the five year requirement for the corresponding Order but who have served at least three years.
There are two versions of this Decoration.
One has the red enamelwork (Official version) the other a plain gilted finish.
The suspension causes many problems with North Vietnamese awards in general and this one is no exception.
Decribed as having a red ribbon with one yellow stripe in Ed's book, so what distinguishes the first and second classes? The image below shows two yellow stripes with a star.
Following the other rules on ribbons for various awards I would tend to think two stripes would be the first class, one stripe the second and the star was added for show as is often the case.

[CtahhR]

The Victory Decoration (Huy Chương Chiến Thắng) was created on 2nd February 1958 in two classes. It ceased to exist on 26th November 2003.

The First Class was awarded for three years service as a field officer. The Second Class was awarded for three years service as an NCO, unless they served before 20th July 1954, where it was for one years' service or any length of service during the Winter-Spring Offensive of 1953-54 (which includes the Battle Of Điện Biên Phủ).

This is an earlier example Second Class.