What does take an extra 50% off redlines mean, in hollister?

I got an email saying that its 50% off redlines? what are redlines? I went into clearance and there not 50% off and in the normal prices there not 50% off either? And it also says online list price reflects 50% discount? I am so confused. Like online do I take off 50% off of the price they have or.. is it the price i have to pay?