The game uses a type of Chinese money-suited pack consisting of 120 cards. The head and foot of the card gives the rank and suit in Chinese characters. During French colonial rule, the Marseilles firm Camoin redesigned the deck to depict people wearing traditional Japanese costumes from the Edo period. There are three suits: Cash (文, Văn), Strings of Cash (索, Sách), and Myriads of Strings (萬, Vạn). Each suit is divided into ten ranks with the highest cards being the Half Cash, Zero String, and Old Man respectively. There are four copies of each card unlike its four-suited kin, Bài bất.
There are five players who each have to draw and discard to form a hand of twenty-one cards. Like Khanhoo, melds are divided into certain types:
- three or four identical cards
- a run of three cards in the same suit
- three cards of the same rank but each from a different suit
In addition there are special melds:
- 1, 2, 3 Cash (not really special but traditionally listed as one)
- 9 Cash, 1 String, 1 Myriad
- 8 Cash, 2 Strings, 2 Myriad
- 7 Cash, 3 Strings, 3 Myriad
- Zero String, 9 Strings, 9 Myriad
- Zero String, 9 Strings, Old man
- Half Cash, 8 Strings, 9 Myriad
- Mark W. McLeod, Thi Dieu Nguyen Culture and Customs of Vietnam 2001- Page 164 "called to tom, or "shrimps' nest" (a modernized version is known in the West as mah-jongg) were extremely popular .."
- Phương Quỳnh Đỗ Traditional festivals in Vietnam 1995 "A number of games and cultural items are performed during the Festival days, at the yard of the communal house: cabaret song performances, human chess (human beings play the role of chess men), the "to tom" card game involving watch-towers, a flower dance (after the dance, flowers are thrown out and people try to snatch them as symbols of good luck).."
- Pollett, Andrea. Vietnam at Andy's Playing Cards. Retrieved 22 May 2016.