For those times when the outcome is strictly pass/fail (but you're just too extra to pull out an actual coin).

Full list in this set: D20 D20 - Large Dice Set Dice Set - Large

All "standard size" dice are scaled to match a 22mm D20 (measured from opposite corners), and all "large" dice are likewise scaled to a 30mm D20.

See also: All Ones D20 All Twenties D20 One Twenty D20 One One D20