Belankas (or Belankai) is the Malay name for the King Crab, one of the pictures featured in the game.
The game consists of a four-sided tee-totum. Modern Belankai spinners are made from a thin wooden dowel
that runs through a cuboid piece of plastic with the pictures engraved on four sides.
The pictures are a king crab, a flower/star/coin (hard to tell - the pictures are all stylized), a fish and a prawn (similar to Hoo-Hey-How).
A staking board is drawn on any large piece of paper (or the ground) showing the four symbols.
Players stake on the pictures and the banker (who will claim the stakes or pay winnings) spins the tee-totum in wide dish and covers it with a bowl.
When the tee-totum comes to rest, it is revealed and players are payed according to whichever picture has come to rest on top.

[0623 x2] Belankai spinner, China, plastic, 53 mm

[0624] Belankai spinner with numbers, plastic, China, 50 mm

[0625 x4] Belankai spinner, China, plastic, 50 mm