A betting structure where bets and raises are fixed to set units.
At $10/$20, the early rounds go in 10s and the later rounds in 20s. Each round allows at most 4 bets: a bet plus 3 raises (the cap). You can't make opponents fold with bet size, so you win with value rather than bluffs. All 5 HORSE games, 2-7 Triple Draw and Badugi use this structure.