black lululemon low cut back tank top

black lululemon low cut tank top- don’t know what the style is called or the exact size but i wear a 4-6 in swiftly techs and other lululemon shirts and it fits perfectly! i would guess a size 4. it has a built in bra along with a low cut back sitting at the perfect length and thick straps. no stains, cuts, tears or discoloring!