The set includes 10 of O.P.Is best selling colours - Alpine Snow, Bubble Bath, Tickle my France-y, Strawberry Margarita, Cajun Shrimp, Big Apple Red, I'm Not Really a Waitress, You Don’t Know Jacques,
Russian Nav, Lincoln Park After Dark
You get a great variation of nudes, brights and darker colours. Now they are minis at only 3.75ml in each bottle. But this way you get to try different colours without spending too much on a colour that you maybe wouldn't like. So if you like one of the colours enough you can just go out and buy the full-size on and knowing that you allready like the colour and will use it.
At the price of £27.50 I think it's a perfect gift for your sister, friend, girlfriend, mom, anyone really =)
I found the set on ASOS, but you can probably find it on multiple online stores.