A double suggesting all-round strength and inviting partner to choose between bidding on and defending for penalties.
At low levels, optional doubles are relatively rare; normally doubles are either definitely penalty or definitely takeout. Optional doubles tend to occur when the opponents have pre-empted to the game level.
![](https://bernardmageebridge.com/wp-content/uploads/2021/11/image-197.png)
On each of these auctions, West’s double is optional.