Thanh Hoa is one of some provinces that found a lot of bronze drums. According to the uncompleted statistics, to present, there have been more than 100 Herger type II bronze drums found in Thanh Hoa province. The Thanh Hoa museum is keeping nearly 70 drums (group B, C, D). Comparing to the H_I bronze drums (Dong Son bronze drums- according to the Herger’s classification, an Austrian scholar), the number of H_II bronze drums (so called Muong’s drums) are equivalent. So, it could be said that Thanh Hoa has biggest collection of bronze drums in .

In the earlier group (group B), around the first millennium AD, the drums have tympanum covering over the barrel and the body could be divided into three manifest parts: Barrel, back and foot that are separated by a flange. Decorative motives on the drums are simple that are mainly geometric patterns, such as: “cereal grain” “honeycomb”, “Comb-teeth”… 30 drums of this type are being kept in Thanh Hoa museum.

   Group C: 13 drums. Characterized by the lost second flange. So, the drum only has the flange that separate the barrel from foot. This flange is in the middle of the drum’s body. The central sun is often in spherical cap-shaped and mostly got eight rays. The central sun is sometimes replaced by lotus flower or multi-petal chrysanthemum. The decoration motives are abundant, not so many “cereal grain” or “concentric-cereal grain” decorative motives, appearing unique motives, such as “dragon”, “bird”, “multi-petal flower”, “lotus petal”, “rolling cloud”, “oak”…

  Goup D - D₂ type: 21 drums. The drums of this type are of equal size. Regarding to the fog figurine, they mostly have four single fog figurines, sometimes double fogs figurine. The central sun is often in spherical cap-shaped, got six to eight rays. The dominated decoration motives are “double oaks”, “coin”, “double lotus leaves” “honeycomb” “birds”. The “double oaks” motif is often decorated on the edge of barrel or foot.

The collection of Herger type II bronze drums in Thanh Hoa museum is valuable resource not only for researchers but also making contribution to the enrichment of the collection of Herger type II bronze drums in .