That is the description on the packet of the new Ernie Ball guitar strings I fitted yesterday and gave an outing to at church this morning. The gauges run from .052 to .010 but with the top strings being relatively light compared to the heavier lower ones. The reason I wanted this combination is that I tune my guitar in 4ths, starting on a low D (an octave up from my six string bass). Since the lower four strings are a tone down from standard tuning, I can put on something a bit thicker without them having too much tension, while the top two are only a semitone down and thus want to be slightly thinner to compensate.
The result? Very satisfactory, with more stable tuning than the previous set (which ran from .046 to .009). All I need to do now is remember to put the spare old strings back in the guitar case — look at my desk tonight, I realise I forgot to put them back in so it is just as well I didn’t have a string breakage incident this morning!