A double, primarily for take out, to convey that the bidder is unwilling to pass but has no good descriptive bid to make. South’s double is competitive in the sequences below.
![](https://bernardmageebridge.com/wp-content/uploads/2021/11/image-47.png)
In the first sequence, it would be pointless for South to attempt a penalty double of a bid that is natural and forcing, especially at such a low level. The double suggests a doubleton heart (not enough hearts to raise to 2♥), a four- or moderate five-card diamond suit (not enough diamonds to be bidding 2♦) and a weakness in one of the black suits (hence the inability to bid 1NT).
This hand would be typical:
![](https://bernardmageebridge.com/wp-content/uploads/2021/11/image-48.png)
In the second sequence, after the opponents have bid and raised spades, it is most unlikely that a worthwhile penalty is available from defending at this level. The double suggests a doubleton heart (not enough hearts to raise to 3♥ or 4♥), five clubs (not enough clubs to bid 3♣) and no spade stopper.
This hand would be typical:
![](https://bernardmageebridge.com/wp-content/uploads/2021/11/image-50.png)
Nowadays, players use many low-level doubles as competitive rather than penalty.