Exclusively for Prime members, Western Digital’s WD_Black C50 1TB Storage Expansion Card for Xbox is on sale at Amazon for $120.64 (about $37 off), very nearly its lowest price to date. You can also get WD’s 512GB card for $65.54 (about $14 off), a few dollars shy of its lowest mark.

Discounts on this powerful Microsoft console can be pretty hard to come by, so there's a good chance that this deal will sell out before it officially expires at 12:59 a.m. ET (9:59 p.m. PT) tonight.

Prime Big Deal Days discounts don’t stop at those on Amazon’s homepage. In fact, Prime members can access a slew of other exclusive promotions that aren't so easy to find. As as a shopping editor who’s been covering Prime Day for five years,