Simple price discount.

[gail]

I have a couple of products that I want to sell at full price for 1 and a discounted price if you buy 2.

(e.g £12 each but 2 for £18)

Is there a way to do this through 'offers' or is a simple drop down menu easier?

I can see 2 for 1 and percentage discounts etc but none that matches what I want.